chore(deps-dev): Update mkdocs-material requirement from ~=9.6.3 to ~=9.6.4 in /gh-pages (#4770)

Updates the requirements on [mkdocs-material](https://github.com/squidfunk/mkdocs-material) to permit the latest version.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/squidfunk/mkdocs-material/releases">mkdocs-material's releases</a>.</em></p>
<blockquote>
<h2>mkdocs-material-9.6.4</h2>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7985">#7985</a>: Blog content sometimes not stretching to full width</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7978">#7978</a>: Navigation rendering bug in Safari 18.3</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG">mkdocs-material's changelog</a>.</em></p>
<blockquote>
<p>mkdocs-material-9.6.4 (2025-02-12)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7985">#7985</a>: Blog content sometimes not stretching to full width</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7978">#7978</a>: Navigation rendering bug in Safari 18.3</li>
</ul>
<p>mkdocs-material-9.6.3 (2025-02-07)</p>
<ul>
<li>Fixed rendering of arrow heads in Mermaid.js class diagrams</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7960">#7960</a>: Tags plugin crashes on numeric metadata titles</li>
</ul>
<p>mkdocs-material-9.6.2 (2025-02-03)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7955">#7955</a>: Excessively long words don't break on narrow screens</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7947">#7947</a>: Scope setting interferes with outdated version banner</li>
</ul>
<p>mkdocs-material-9.6.1 (2025-01-31)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7943">#7943</a>: Tags plugin crashing due to merge error</li>
</ul>
<p>mkdocs-material-9.6.0 (2025-01-31)</p>
<ul>
<li>Added meta plugin</li>
<li>Rewrite of the tags plugin</li>
<li>Added support for allow lists in tags plugin</li>
<li>Added support for and custom sorting in tags plugin</li>
<li>Added support for related links in blog plugin</li>
<li>Added support for custom index pages in blog plugin</li>
<li>Added support for navigation subtitles</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7924">#7924</a>: Anchors might require two clicks when using instant navigation</li>
</ul>
<p>mkdocs-material-9.5.50 (2025-01-18)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7913">#7913</a>: Social plugin renders attribute lists in page title</li>
</ul>
<p>mkdocs-material-9.5.49+insiders-4.53.15 (2025-01-15)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7896">#7896</a>: Scoped tags listings not rendering in subsections</li>
</ul>
<p>mkdocs-material-9.5.49 (2024-12-16)</p>
<ul>
<li>Adjusted title color in dark mode for all supported Mermaid.js diagrams</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7803">#7803</a>: Privacy plugin crashes on generated files</li>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7781">#7781</a>: Mermaid.js flow chart title not visible in dark mode</li>
</ul>
<p>mkdocs-material-9.5.48 (2024-12-08)</p>
<ul>
<li>Fixed <a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7774">#7774</a>: Disabling social cards doesn't work</li>
</ul>
<p>mkdocs-material-9.5.47 (2024-12-01)</p>

</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/9b0f482dbbfc645982ebe78a83e929ca5004e6e8"><code>9b0f482</code></a> Prepare 9.6.4 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/a9bae7f0c732d2167cec346fe9fa1065cbdc5b72"><code>a9bae7f</code></a> Fixed navigation spacing in Safari 18.3 (<a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7979">#7979</a>)</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/9be17e7c67fb6b406e2d4df9174175736026678f"><code>9be17e7</code></a> Documentation (<a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7989">#7989</a>)</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/8a576105fdd21a3d63e1f90c1d33db3908354a99"><code>8a57610</code></a> Fixed blog post content sometimes not stretching</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/10dd00486357d774bb23f385f8fa30ddbfe8278f"><code>10dd004</code></a> Added warning on using Docker in production (<a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7977">#7977</a>)</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/cd2ec69f011669631757f94596c47df1735eab1f"><code>cd2ec69</code></a> Fixed wrong value type for enabled setting in GitHub Actions (<a href="https://redirect.github.com/squidfunk/mkdocs-material/issues/7980">#7980</a>)</li>
<li>See full diff in <a href="https://github.com/squidfunk/mkdocs-material/compare/9.6.3...9.6.4">compare view</a></li>
</ul>
</details>
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gh-pages/requirements-dev.txt

@@ -1,4 +1,4 @@
 mkdocs~=1.6.1
 mkdocs-awesome-pages-plugin~=2.10.1
-mkdocs-material~=9.6.3
+mkdocs-material~=9.6.4
 mkdocs-git-revision-date-plugin~=0.3.2