Bump the known_good_semver group with 2 updates (#2810)

Bumps the known_good_semver group with 2 updates:
[syn](https://github.com/dtolnay/syn) and
[serde_yaml](https://github.com/dtolnay/serde-yaml).

Updates `syn` from 2.0.41 to 2.0.43
<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>2.0.43</h2>
<ul>
<li>Insert trailing comma if not already present when printing a 1-tuple
in pattern position (<a
href="https://redirect.github.com/dtolnay/syn/issues/1553">#1553</a>)</li>
</ul>
<h2>2.0.42</h2>
<ul>
<li>Documentation improvements</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/dtolnay/syn/commit/95ee05214030f936b8db3ee295188d5dc2c89621"><code>95ee052</code></a>
Release 2.0.43</li>
<li><a
href="https://github.com/dtolnay/syn/commit/7383e81b1ab6f9983692ebd9d6caa54aeff8fb85"><code>7383e81</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/syn/issues/1559">#1559</a>
from dtolnay/pattuple</li>
<li><a
href="https://github.com/dtolnay/syn/commit/712fde5a6fce0e7bee3615ab5c7545ce442bf034"><code>712fde5</code></a>
Fix ToTokens for PatTuple to insert trailing comma</li>
<li><a
href="https://github.com/dtolnay/syn/commit/ed9b94e3395cffb33db4254439e23dbc3a2e9e43"><code>ed9b94e</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/syn/issues/1558">#1558</a>
from dtolnay/tupletests</li>
<li><a
href="https://github.com/dtolnay/syn/commit/ec8517b33c137c48c38b74ba5be21815763a50f5"><code>ec8517b</code></a>
Add tuple comma tests</li>
<li><a
href="https://github.com/dtolnay/syn/commit/3cf16c76bdbe4e16261a167592a77edab853c6aa"><code>3cf16c7</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/syn/issues/1557">#1557</a>
from dtolnay/snapshotparsequote</li>
<li><a
href="https://github.com/dtolnay/syn/commit/553549ff12358a6ad95baaed2601a9dab541d693"><code>553549f</code></a>
Generalize snapshot parsing to types that do not implement Parse</li>
<li><a
href="https://github.com/dtolnay/syn/commit/f9ad833e4a77c61003861f4e14d16b10b9708f9e"><code>f9ad833</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/syn/issues/1556">#1556</a>
from dtolnay/punctuatedsnapshot</li>
<li><a
href="https://github.com/dtolnay/syn/commit/131b40ba2904ec8755bb34466f369072dc34d588"><code>131b40b</code></a>
Debug impl for punctuated::Pairs superseded by Punctuated</li>
<li><a
href="https://github.com/dtolnay/syn/commit/3f12d652a8871955a7e27e0369933288bc387dd5"><code>3f12d65</code></a>
Include punctuation tokens in snapshot tests containing Punctuated</li>
<li>Additional commits viewable in <a
href="https://github.com/dtolnay/syn/compare/2.0.41...2.0.43">compare
view</a></li>
</ul>
</details>
<br />

Updates `serde_yaml` from 0.9.27 to 0.9.29
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/dtolnay/serde-yaml/releases">serde_yaml's
releases</a>.</em></p>
<blockquote>
<h2>0.9.29</h2>
<ul>
<li>Turn on <code>deny(unsafe_op_in_unsafe_fn)</code> lint</li>
</ul>
<h2>0.9.28</h2>
<ul>
<li>Update <code>unsafe-libyaml</code> dependency to pull in unaligned
write fix</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/b957d2b15d7f3d96279997800fa0610b41b8fe00"><code>b957d2b</code></a>
Release 0.9.29</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/007fc2d5c1987847a0f1ac95885c56f8e6e5f808"><code>007fc2d</code></a>
Merge pull request <a
href="https://redirect.github.com/dtolnay/serde-yaml/issues/401">#401</a>
from dtolnay/unsafeop</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/5bac2475b0017d6a635d641df17165d71b951f0e"><code>5bac247</code></a>
Fill in unsafe blocks inside unsafe functions</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/0f6dba18ab8db598c4963e9242afd490ee0202f0"><code>0f6dba1</code></a>
Turn on deny(unsafe_op_in_unsafe_fn)</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/1b6e44837f0db0a1c15537311fed3579a7e8c6d2"><code>1b6e448</code></a>
Release 0.9.28</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/ec1a3145d7b6b809f7b3aa2d9dcd7db30f0588d4"><code>ec1a314</code></a>
Force unsafe-libyaml version that contains unaligned write fix</li>
<li><a
href="https://github.com/dtolnay/serde-yaml/commit/a6b2dc075a6eb1bed0d927df7b7ac2bb288f3bb4"><code>a6b2dc0</code></a>
Update name of blocks_in_if_conditions clippy lint</li>
<li>See full diff in <a
href="https://github.com/dtolnay/serde-yaml/compare/0.9.27...0.9.29">compare
view</a></li>
</ul>
</details>
<br />


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