chore(deps): Bump darling from 0.20.1 to 0.20.3 (vectordotdev#17969)

Bumps [darling](https://github.com/TedDriggs/darling) from 0.20.1 to
0.20.3.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/TedDriggs/darling/releases">darling's
releases</a>.</em></p>
<blockquote>
<h2>v0.20.3</h2>
<ul>
<li>Add <code>FromMeta</code> impl for <code>u128</code> and
<code>i128</code> <a
href="https://redirect.github.com/TedDriggs/darling/pull/243">#243</a></li>
</ul>
<p>This release also includes features originally slated for 0.20.2, as
that was never published.</p>
<ul>
<li>Allow darling users to omit quotation marks for paths and idents <a
href="https://redirect.github.com/TedDriggs/darling/pull/236">#236</a></li>
<li>Add new util functions for controlling how quotation marks are
handled when reading into <code>Expr</code> fields <a
href="https://redirect.github.com/TedDriggs/darling/pull/235">#235</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/TedDriggs/darling/blob/master/CHANGELOG.md">darling's
changelog</a>.</em></p>
<blockquote>
<h2>v0.20.3 (July 12, 2023)</h2>
<ul>
<li>Add <code>FromMeta</code> impl for <code>u128</code> and
<code>i128</code> <a
href="https://redirect.github.com/TedDriggs/darling/pull/243">#243</a></li>
</ul>
<h2>v0.20.2 (May 25, 2023)</h2>
<ul>
<li>Allow darling users to omit quotation marks for paths and idents <a
href="https://redirect.github.com/TedDriggs/darling/pull/236">#236</a></li>
<li>Add new util functions for controlling how quotation marks are
handled when reading into <code>Expr</code> fields <a
href="https://redirect.github.com/TedDriggs/darling/pull/235">#235</a></li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/TedDriggs/darling/commit/99ae0bb97fd88f4b22dd46b95773a1e752bfcf34"><code>99ae0bb</code></a>
Bump version to 0.20.3</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/7928941075bab9b474288cd950349f43b02d14b9"><code>7928941</code></a>
Implement FromMeta for i128 and u128</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/8c4d6adca2d71c4f80da019fef5bd6366a6c8bfe"><code>8c4d6ad</code></a>
Fix clippy violation</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/371dd9baee334f1098aecc465f84bb9996adb672"><code>371dd9b</code></a>
Bump version to 0.20.2</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/6d6f6e015f0dace091a187fdbdb7a66559ea5796"><code>6d6f6e0</code></a>
Add new parsing util functions for Exprs</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/9bdda12f704978aff19de2b2f7011679c9019e0d"><code>9bdda12</code></a>
Accept paths and idents without quotation marks in value positions</li>
<li><a
href="https://github.com/TedDriggs/darling/commit/6f15cc3758d638a5916a02bd34c5976ff19295e8"><code>6f15cc3</code></a>
Update README.md</li>
<li>See full diff in <a
href="https://github.com/TedDriggs/darling/compare/v0.20.1...v0.20.3">compare
view</a></li>
</ul>
</details>
<br />


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