Bumps [rand](https://github.com/rust-random/rand) from 0.7.3 to 0.8.5.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/rust-random/rand/blob/master/CHANGELOG.md">rand's
changelog</a>.</em></p>
<blockquote>
<h2>[0.8.5] - 2021-08-20</h2>
<h3>Fixes</h3>
<ul>
<li>Fix build on non-32/64-bit architectures (<a
href="https://redirect.github.com/rust-random/rand/issues/1144">#1144</a>)</li>
<li>Fix &quot;min_const_gen&quot; feature for <code>no_std</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1173">#1173</a>)</li>
<li>Check <code>libc::pthread_atfork</code> return value with panic on
error (<a
href="https://redirect.github.com/rust-random/rand/issues/1178">#1178</a>)</li>
<li>More robust reseeding in case <code>ReseedingRng</code> is used from
a fork handler (<a
href="https://redirect.github.com/rust-random/rand/issues/1178">#1178</a>)</li>
<li>Fix nightly: remove unused <code>slice_partition_at_index</code>
feature (<a
href="https://redirect.github.com/rust-random/rand/issues/1215">#1215</a>)</li>
<li>Fix nightly + <code>simd_support</code>: update
<code>packed_simd</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1216">#1216</a>)</li>
</ul>
<h3>Rngs</h3>
<ul>
<li><code>StdRng</code>: Switch from HC128 to ChaCha12 on emscripten (<a
href="https://redirect.github.com/rust-random/rand/issues/1142">#1142</a>).
We now use ChaCha12 on all platforms.</li>
</ul>
<h3>Documentation</h3>
<ul>
<li>Added docs about rand's use of const generics (<a
href="https://redirect.github.com/rust-random/rand/issues/1150">#1150</a>)</li>
<li>Better random chars example (<a
href="https://redirect.github.com/rust-random/rand/issues/1157">#1157</a>)</li>
</ul>
<h2>[0.8.4] - 2021-06-15</h2>
<h3>Additions</h3>
<ul>
<li>Use const-generics to support arrays of all sizes (<a
href="https://redirect.github.com/rust-random/rand/issues/1104">#1104</a>)</li>
<li>Implement <code>Clone</code> and <code>Copy</code> for
<code>Alphanumeric</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1126">#1126</a>)</li>
<li>Add <code>Distribution::map</code> to derive a distribution using a
closure (<a
href="https://redirect.github.com/rust-random/rand/issues/1129">#1129</a>)</li>
<li>Add <code>Slice</code> distribution (<a
href="https://redirect.github.com/rust-random/rand/issues/1107">#1107</a>)</li>
<li>Add <code>DistString</code> trait with impls for
<code>Standard</code> and <code>Alphanumeric</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1133">#1133</a>)</li>
</ul>
<h3>Other</h3>
<ul>
<li>Reorder asserts in <code>Uniform</code> float distributions for
easier debugging of non-finite arguments
(<a
href="https://redirect.github.com/rust-random/rand/issues/1094">#1094</a>,
<a
href="https://redirect.github.com/rust-random/rand/issues/1108">#1108</a>)</li>
<li>Add range overflow check in <code>Uniform</code> float distributions
(<a
href="https://redirect.github.com/rust-random/rand/issues/1108">#1108</a>)</li>
<li>Deprecate <code>rngs::adapter::ReadRng</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1130">#1130</a>)</li>
</ul>
<h2>[0.8.3] - 2021-01-25</h2>
<h3>Fixes</h3>
<ul>
<li>Fix <code>no-std</code> + <code>alloc</code> build by gating
<code>choose_multiple_weighted</code> on <code>std</code> (<a
href="https://redirect.github.com/rust-random/rand/issues/1088">#1088</a>)</li>
</ul>
<h2>[0.8.2] - 2021-01-12</h2>
<h3>Fixes</h3>
<ul>
<li>Fix panic in <code>UniformInt::sample_single_inclusive</code> and
<code>Rng::gen_range</code> when
providing a full integer range (eg <code>0..=MAX</code>) (<a
href="https://redirect.github.com/rust-random/rand/issues/1087">#1087</a>)</li>
</ul>
<h2>[0.8.1] - 2020-12-31</h2>
<h3>Other</h3>
<ul>
<li>Enable all stable features in the playground (<a
href="https://redirect.github.com/rust-random/rand/issues/1081">#1081</a>)</li>
</ul>
<h2>[0.8.0] - 2020-12-18</h2>
<h3>Platform support</h3>
<ul>
<li>The minimum supported Rust version is now 1.36 (<a
href="https://redirect.github.com/rust-random/rand/issues/1011">#1011</a>)</li>
<li><code>getrandom</code> updated to v0.2 (<a
href="https://redirect.github.com/rust-random/rand/issues/1041">#1041</a>)</li>
<li>Remove <code>wasm-bindgen</code> and <code>stdweb</code> feature
flags. For details of WASM support,</li>
</ul>
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</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/rust-random/rand/commit/937320cbfeebd4352a23086d9c6e68f067f74644"><code>937320c</code></a>
Update CHANGELOG for 0.8.5 (<a
href="https://redirect.github.com/rust-random/rand/issues/1221">#1221</a>)</li>
<li><a
href="https://github.com/rust-random/rand/commit/2924af688d352b889322870d017356f12651866b"><code>2924af6</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-random/rand/issues/1183">#1183</a>
from vks/fill-float-doc</li>
<li><a
href="https://github.com/rust-random/rand/commit/dbbc1bf3176138c867f3d84c0c4d288119a5a84e"><code>dbbc1bf</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-random/rand/issues/1218">#1218</a>
from Will-Low/master</li>
<li><a
href="https://github.com/rust-random/rand/commit/9f20df04d88698c38515833d6db62d7eb50d8b80"><code>9f20df0</code></a>
Making distributions comparable by deriving PartialEq. Tests
included</li>
<li><a
href="https://github.com/rust-random/rand/commit/a407bdfa4563d0cfbf744049242926c8de079d3f"><code>a407bdf</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-random/rand/issues/1216">#1216</a>
from rust-random/work5</li>
<li><a
href="https://github.com/rust-random/rand/commit/d3ca11b0bcc1f42fe34ba4f90f99509b7eb4ff18"><code>d3ca11b</code></a>
Update to packed_simd_2 0.3.7</li>
<li><a
href="https://github.com/rust-random/rand/commit/fa04c15d0bb5842fdbdbb73d7a53ead36f3fcf52"><code>fa04c15</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-random/rand/issues/1215">#1215</a>
from Lantern-chat/master</li>
<li><a
href="https://github.com/rust-random/rand/commit/73f8ffd16379390e624ac53cd6882dd679dd9a6f"><code>73f8ffd</code></a>
Remove unused <code>slice_partition_at_index</code> feature</li>
<li><a
href="https://github.com/rust-random/rand/commit/8f372500f05dfadcff6c35e773e81029ab7debad"><code>8f37250</code></a>
Merge pull request <a
href="https://redirect.github.com/rust-random/rand/issues/1208">#1208</a>
from newpavlov/rand_distr/fix_no_std</li>
<li><a
href="https://github.com/rust-random/rand/commit/9ef737ba5b814f6ab36cebafb59ad29885d68a05"><code>9ef737b</code></a>
update changelog</li>
<li>Additional commits viewable in <a
href="https://github.com/rust-random/rand/compare/0.7.3...0.8.5">compare
view</a></li>
</ul>
</details>
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