Bump lints from 5.1.1 to 6.0.0 in /code_sharing/server (#2619)

Bumps [lints](https://github.com/dart-lang/core/tree/main/pkgs) from 5.1.1 to 6.0.0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/dart-lang/core/releases">lints's releases</a>.</em></p>
<blockquote>
<h2>package:lints v6.0.0</h2>
<ul>
<li><code>core</code>:
<ul>
<li>added <a href="https://dart.dev/lints/strict_top_level_inference">strict_top_level_inference</a> (<a href="https://redirect.github.com/dart-lang/core/issues/836">dart-lang/core#836</a>)</li>
</ul>
</li>
<li><code>recommended</code>:
<ul>
<li>added <a href="https://dart.dev/lints/unnecessary_underscores">unnecessary_underscores</a> (<a href="https://redirect.github.com/dart-lang/core/issues/856">dart-lang/core#856</a>)</li>
</ul>
</li>
<li>Require Dart 3.8.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/dart-lang/core/commit/228112c0868d08066fcad15f14c5ace5e5e1b995"><code>228112c</code></a> prep to publish 6.0.0 of package:lints (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/878">#878</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/e32c7b96b980179bdea103846f0f4498506093df"><code>e32c7b9</code></a> Fix StreamGroup.broadcast() close() not completing when streams close. (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/876">#876</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/af37fe54c320b0f76f76da01acbbfc0c0118e613"><code>af37fe5</code></a> Adds <code>[Heap]PriorityQueue.of</code> constructor. (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/734">#734</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/635dfa32c261ba078438b74de397f2207904ca78"><code>635dfa3</code></a> [collection] explicitly make BoolList abstract interface (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/875">#875</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/a6e81e0b74faf12ed4a938fa9a8ddba86b89b73d"><code>a6e81e0</code></a> Make URL strategy better at recognizing URLs. (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/873">#873</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/61e677100b06d56a1b3731ab1178ebf9102ecb1f"><code>61e6771</code></a> Check for mandatory when using option (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/871">#871</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/db610bb59554707a2be47e1082a8b7c85fe87f18"><code>db610bb</code></a> Adjust the implements clause of IntX (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/866">#866</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/22d8879fcb6705290270607d9de7c4dc4ff79a94"><code>22d8879</code></a> [package:lints] fix the changelog (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/867">#867</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/9f4321008457d16674c0faabfe49327a2bb0cd29"><code>9f43210</code></a> add strict_top_level_inference to the core lint set (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/864">#864</a>)</li>
<li><a href="https://github.com/dart-lang/core/commit/15c7fe9958b95998ba2f5a4ad1beab66b9d815fb"><code>15c7fe9</code></a> add unnecessary_underscores to recommended (<a href="https://github.com/dart-lang/core/tree/main/pkgs/issues/863">#863</a>)</li>
<li>Additional commits viewable in <a href="https://github.com/dart-lang/core/commits/lints-v6.0.0/pkgs">compare view</a></li>
</ul>
</details>
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Author: dependabot[bot]

code_sharing/server/pubspec.yaml

@@ -15,5 +15,5 @@ dependencies:
 
 dev_dependencies:
   http: ^1.0.0
-  lints: ^5.0.0
+  lints: ^6.0.0
   test: ^1.15.0