Bumps the known_good_semver group with 3 updates:
[log](https://github.com/rust-lang/log),
[syn](https://github.com/dtolnay/syn) and
[clap](https://github.com/clap-rs/clap).

Updates `log` from 0.4.20 to 0.4.21
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/rust-lang/log/blob/master/CHANGELOG.md">log's
changelog</a>.</em></p>
<blockquote>
<h2>[0.4.21] - 2024-02-27</h2>
<h2>What's Changed</h2>
<ul>
<li>Minor clippy nits by <a
href="https://github.com/nyurik"><code>@​nyurik</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/578">rust-lang/log#578</a></li>
<li>Simplify Display impl by <a
href="https://github.com/nyurik"><code>@​nyurik</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/579">rust-lang/log#579</a></li>
<li>Set all crates to 2021 edition by <a
href="https://github.com/nyurik"><code>@​nyurik</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/580">rust-lang/log#580</a></li>
<li>Various changes based on review by <a
href="https://github.com/Thomasdezeeuw"><code>@​Thomasdezeeuw</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/583">rust-lang/log#583</a></li>
<li>Fix typo in file_static() method doc by <a
href="https://github.com/dimo414"><code>@​dimo414</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/590">rust-lang/log#590</a></li>
<li>Specialize empty key value pairs by <a
href="https://github.com/EFanZh"><code>@​EFanZh</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/576">rust-lang/log#576</a></li>
<li>Fix incorrect lifetime in Value::to_str() by <a
href="https://github.com/peterjoel"><code>@​peterjoel</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/587">rust-lang/log#587</a></li>
<li>Remove some API of the key-value feature by <a
href="https://github.com/Thomasdezeeuw"><code>@​Thomasdezeeuw</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/585">rust-lang/log#585</a></li>
<li>Add logcontrol-log and log-reload by <a
href="https://github.com/swsnr"><code>@​swsnr</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/595">rust-lang/log#595</a></li>
<li>Add Serialization section to kv::Value docs by <a
href="https://github.com/Thomasdezeeuw"><code>@​Thomasdezeeuw</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/593">rust-lang/log#593</a></li>
<li>Rename Value::to_str to to_cow_str by <a
href="https://github.com/Thomasdezeeuw"><code>@​Thomasdezeeuw</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/592">rust-lang/log#592</a></li>
<li>Clarify documentation and simplify initialization of
<code>STATIC_MAX_LEVEL</code> by <a
href="https://github.com/ptosi"><code>@​ptosi</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/594">rust-lang/log#594</a></li>
<li>Update docs to 2021 edition, test by <a
href="https://github.com/nyurik"><code>@​nyurik</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/577">rust-lang/log#577</a></li>
<li>Add &quot;alterable_logger&quot; link to README.md by <a
href="https://github.com/brummer-simon"><code>@​brummer-simon</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/589">rust-lang/log#589</a></li>
<li>Normalize line ending by <a
href="https://github.com/EFanZh"><code>@​EFanZh</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/602">rust-lang/log#602</a></li>
<li>Remove <code>ok_or</code> in favor of <code>Option::ok_or</code> by
<a
href="https://github.com/AngelicosPhosphoros"><code>@​AngelicosPhosphoros</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/607">rust-lang/log#607</a></li>
<li>Use <code>Acquire</code> ordering for initialization check by <a
href="https://github.com/AngelicosPhosphoros"><code>@​AngelicosPhosphoros</code></a>
in <a
href="https://redirect.github.com/rust-lang/log/pull/610">rust-lang/log#610</a></li>
<li>Get structured logging API ready for stabilization by <a
href="https://github.com/KodrAus"><code>@​KodrAus</code></a> in <a
href="https://redirect.github.com/rust-lang/log/pull/613">rust-lang/log#613</a></li>
</ul>
<h2>New Contributors</h2>
<ul>
<li><a href="https://github.com/nyurik"><code>@​nyurik</code></a> made
their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/578">rust-lang/log#578</a></li>
<li><a href="https://github.com/dimo414"><code>@​dimo414</code></a> made
their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/590">rust-lang/log#590</a></li>
<li><a href="https://github.com/peterjoel"><code>@​peterjoel</code></a>
made their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/587">rust-lang/log#587</a></li>
<li><a href="https://github.com/ptosi"><code>@​ptosi</code></a> made
their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/594">rust-lang/log#594</a></li>
<li><a
href="https://github.com/brummer-simon"><code>@​brummer-simon</code></a>
made their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/589">rust-lang/log#589</a></li>
<li><a
href="https://github.com/AngelicosPhosphoros"><code>@​AngelicosPhosphoros</code></a>
made their first contribution in <a
href="https://redirect.github.com/rust-lang/log/pull/607">rust-lang/log#607</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/rust-lang/log/commit/3ccdc286fef3076747fe18a2a93658ea4d4ae012"><code>3ccdc28</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-lang/log/issues/617">#617</a>
from rust-lang/cargo/0.4.21</li>
<li><a
href="https://github.com/rust-lang/log/commit/6153cb289f0e7b80f00ae07dbe5ee41cf3d3fcb0"><code>6153cb2</code></a>
prepare for 0.4.21 release</li>
<li><a
href="https://github.com/rust-lang/log/commit/f0f74946a4bfb02cfc407795a3499c4b69d7a290"><code>f0f7494</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-lang/log/issues/613">#613</a>
from rust-lang/feat/kv-cleanup</li>
<li><a
href="https://github.com/rust-lang/log/commit/2b220bf3b705f2abc0ee591c7eb17972a979da3a"><code>2b220bf</code></a>
clean up structured logging example</li>
<li><a
href="https://github.com/rust-lang/log/commit/646e9ab9917fb79e44b6b36b8375106a1a09766c"><code>646e9ab</code></a>
use original Visitor name for VisitValue</li>
<li><a
href="https://github.com/rust-lang/log/commit/cf85c38d3519745d60e7b891c4b2025050a8389f"><code>cf85c38</code></a>
add needed subfeatures to kv_unstable</li>
<li><a
href="https://github.com/rust-lang/log/commit/73e953905b970ef765a86bf6cbd69bc2c5e2bac4"><code>73e9539</code></a>
fix up capturing of :err</li>
<li><a
href="https://github.com/rust-lang/log/commit/31bb4b0ff36e458c6bef304a336b71f6342ddcc7"><code>31bb4b0</code></a>
move error macros together</li>
<li><a
href="https://github.com/rust-lang/log/commit/ad917118a5e781d0dd60b3a75ba519ce9839ba70"><code>ad91711</code></a>
support field shorthand in macros</li>
<li><a
href="https://github.com/rust-lang/log/commit/90a347bd836873264a393a35bfd90fe478fadae2"><code>90a347b</code></a>
restore removed APIs as deprecated</li>
<li>Additional commits viewable in <a
href="https://github.com/rust-lang/log/compare/0.4.20...0.4.21">compare
view</a></li>
</ul>
</details>
<br />

Updates `syn` from 2.0.50 to 2.0.52
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/dtolnay/syn/releases">syn's
releases</a>.</em></p>
<blockquote>
<h2>2.0.52</h2>
<ul>
<li>Add an expression parser that uses match-arm's boundary rules (<a
href="https://redirect.github.com/dtolnay/syn/issues/1593">#1593</a>)</li>
</ul>
<h2>2.0.51</h2>
<ul>
<li>Resolve non_local_definitions warnings in generated code under rustc
1.78-nightly</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/dtolnay/syn/commit/07ede6a6b31adeb3a18899ada1f352f63b3a36b9"><code>07ede6a</code></a>
Release 2.0.52</li>
<li><a
href="https://github.com/dtolnay/syn/commit/acbcfbc8c113fa1603469c9ad329d061ee74662e"><code>acbcfbc</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/syn/issues/1593">#1593</a>
from dtolnay/boundary</li>
<li><a
href="https://github.com/dtolnay/syn/commit/4924a993dce23abe65128ac318dd662d1e2ceef2"><code>4924a99</code></a>
Add an expression parser that uses match-arm's boundary rules</li>
<li><a
href="https://github.com/dtolnay/syn/commit/e06122bf2cfd31bd7f70304694477dd292fe7e1e"><code>e06122b</code></a>
Resolve unnecessary_get_then_check clippy lint</li>
<li><a
href="https://github.com/dtolnay/syn/commit/018fc5a6298491525387910cb359a9ec618abe54"><code>018fc5a</code></a>
Update test suite to nightly-2024-02-27</li>
<li><a
href="https://github.com/dtolnay/syn/commit/5e15a9b412cb1e2df481e3470e1be8defaee4495"><code>5e15a9b</code></a>
Release 2.0.51</li>
<li><a
href="https://github.com/dtolnay/syn/commit/7e0d4e1f43a879078595f0a3876484a1920ab8f8"><code>7e0d4e1</code></a>
Resolve non_local_definitions warning in debug impls</li>
<li><a
href="https://github.com/dtolnay/syn/commit/8667ad97c1d4e75ac1bb323fb5c7849269814145"><code>8667ad9</code></a>
Ignore module_name_repetitions pedantic clippy lint in codegen</li>
<li><a
href="https://github.com/dtolnay/syn/commit/1fc32000e25bf8fda7371071073f91e012ddf808"><code>1fc3200</code></a>
Update test suite to nightly-2024-02-26</li>
<li><a
href="https://github.com/dtolnay/syn/commit/07a2065576b27dcf0c104f56379cc446d2f3824b"><code>07a2065</code></a>
Update test suite to nightly-2024-02-23</li>
<li>See full diff in <a
href="https://github.com/dtolnay/syn/compare/2.0.50...2.0.52">compare
view</a></li>
</ul>
</details>
<br />

Updates `clap` from 4.5.1 to 4.5.3
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/clap-rs/clap/releases">clap's
releases</a>.</em></p>
<blockquote>
<h2>v4.5.3</h2>
<h2>[4.5.3] - 2024-03-15</h2>
<h3>Internal</h3>
<ul>
<li><em>(derive)</em> Update <code>heck</code></li>
</ul>
<h2>v4.5.2</h2>
<h2>[4.5.2] - 2024-03-06</h2>
<h3>Fixes</h3>
<ul>
<li><em>(macros)</em> Silence a warning</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/clap-rs/clap/blob/master/CHANGELOG.md">clap's
changelog</a>.</em></p>
<blockquote>
<h2>[4.5.3] - 2024-03-15</h2>
<h3>Internal</h3>
<ul>
<li><em>(derive)</em> Update <code>heck</code></li>
</ul>
<h2>[4.5.2] - 2024-03-06</h2>
<h3>Fixes</h3>
<ul>
<li><em>(macros)</em> Silence a warning</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/clap-rs/clap/commit/4e07b438584bb8a19e37599d4c5b11797bec5579"><code>4e07b43</code></a>
chore: Release</li>
<li><a
href="https://github.com/clap-rs/clap/commit/8247c7ddf05d8023729ac180d8e8df260f1da5ff"><code>8247c7d</code></a>
docs: Update changelog</li>
<li><a
href="https://github.com/clap-rs/clap/commit/677c52ce0870115845a4c42e204f6c049b81a1e7"><code>677c52c</code></a>
chore: Update <code>heck</code> requirement (<a
href="https://redirect.github.com/clap-rs/clap/issues/5396">#5396</a>)</li>
<li><a
href="https://github.com/clap-rs/clap/commit/f65d421607ba16c3175ffe76a20820f123b6c4cb"><code>f65d421</code></a>
chore: Release</li>
<li><a
href="https://github.com/clap-rs/clap/commit/886b2729e419114bf42f1a92c66d346c81aa8f33"><code>886b272</code></a>
docs: Update changelog</li>
<li><a
href="https://github.com/clap-rs/clap/commit/3ba429752fdb19b7a1c2e151c41d5141ad5b9295"><code>3ba4297</code></a>
Merge pull request <a
href="https://redirect.github.com/clap-rs/clap/issues/5386">#5386</a>
from amaanq/static-var-name</li>
<li><a
href="https://github.com/clap-rs/clap/commit/2aea9504c4894b3bddf9cd4d2d6cba889307c157"><code>2aea950</code></a>
fix: Use SCREAMING_SNAKE_CASE for static variable
<code>authors</code></li>
<li><a
href="https://github.com/clap-rs/clap/commit/690f5557d7f25904c31ec9f2a3c3657cbb68c98e"><code>690f555</code></a>
Merge pull request <a
href="https://redirect.github.com/clap-rs/clap/issues/5382">#5382</a>
from clap-rs/renovate/pre-commit-action-3.x</li>
<li><a
href="https://github.com/clap-rs/clap/commit/a2aa644368ec19026b16b870ec32dc57b325ba9b"><code>a2aa644</code></a>
chore(deps): update compatible (dev) (<a
href="https://redirect.github.com/clap-rs/clap/issues/5381">#5381</a>)</li>
<li><a
href="https://github.com/clap-rs/clap/commit/c233de53c0cca4281f444cf16d16d161bc9c3cab"><code>c233de5</code></a>
chore(deps): update pre-commit/action action to v3.0.1</li>
<li>Additional commits viewable in <a
href="https://github.com/clap-rs/clap/compare/clap_complete-v4.5.1...v4.5.3">compare
view</a></li>
</ul>
</details>
<br />


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