chore(deps-dev): bump mkdocs-material from 7.2.6 to 7.2.8 (#682)

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 7.2.6 to 7.2.8.
<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-7.2.8</h2>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/3039">#3039</a>: Search modal overlays menu on mobile (7.2.7 regression)</li>
</ul>
<h2>mkdocs-material-7.2.7</h2>
<ul>
<li>Updated Serbian and Serbo-Croatian translations</li>
<li>Improved appearance of outline on details</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/2934">#2934</a>: Scrollbar when header is hidden on some mobile browsers</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/3032">#3032</a>: Anchor in details doesn't open on load (7.0.0 regression)</li>
<li>Fixed back-to-top button being focusable when invisible</li>
<li>Fixed broken admonition icons (removed in upstream)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/squidfunk/mkdocs-material/blob/master/docs/changelog.md">mkdocs-material's changelog</a>.</em></p>
<blockquote>
<h3>7.2.8 <!-- raw HTML omitted -->_ September 20, 2021<!-- raw HTML omitted --></h3>
<ul>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/3039">#3039</a>: Search modal overlays menu on mobile (7.2.7 regression)</li>
</ul>
<h3>7.2.7 <!-- raw HTML omitted -->_ September 19, 2021<!-- raw HTML omitted --></h3>
<ul>
<li>Updated Serbian and Serbo-Croatian translations</li>
<li>Improved appearance of outline on details</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/2934">#2934</a>: Scrollbar when header is hidden on some mobile browsers</li>
<li>Fixed <a href="https://github-redirect.dependabot.com/squidfunk/mkdocs-material/issues/3032">#3032</a>: Anchor in details doesn't open on load (7.0.0 regression)</li>
<li>Fixed back-to-top button being focusable when invisible</li>
<li>Fixed broken admonition icons (removed in upstream)</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/166096d45459dc67b7e8d333e4cf692064f1ad78"><code>166096d</code></a> Prepare 7.2.8 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/2eabc94e5e650eb96d9cff0e66290a643087f0d4"><code>2eabc94</code></a> Fixed search modal overlaying menu on mobile (7.2.7 regression)</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/ea130d1f311440543dbd7de0877a54cfaf7b9160"><code>ea130d1</code></a> Added documentation for third-party Docker image</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/96cc7b67694387450f535f52cc5f06896b15e383"><code>96cc7b6</code></a> Updated Insiders changelog</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/e580eb205f5e0530eb68e53695d85881067e8343"><code>e580eb2</code></a> Updated Insiders changelog</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/7c0a2512fb18cc10205613c2ee60fc7e618adc6a"><code>7c0a251</code></a> Prepare 7.2.7 release</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/36f1e99f3c94db3538e3d9191b328f4825c976ed"><code>36f1e99</code></a> Updated dependencies</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/749558983054e571f42c7e402c9c978b211185cf"><code>7495589</code></a> Added distribution files</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/090d0edc5972aec02e622ce594b4dbd6acd04360"><code>090d0ed</code></a> Improved Serbian translations</li>
<li><a href="https://github.com/squidfunk/mkdocs-material/commit/d678678cc45372cc1313dde394abbd8c73bebfa9"><code>d678678</code></a> Fixed scrollbar on mobile when header is hidden on some browsers</li>
<li>Additional commits viewable in <a href="https://github.com/squidfunk/mkdocs-material/compare/7.2.6...7.2.8">compare view</a></li>
</ul>
</details>
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Author: dependabot[bot]

Diff for: poetry.lock

@@ -50,7 +50,7 @@ radon = "^5.1.0"
 xenon = "^0.8.0"
 flake8-eradicate = "^1.1.0"
 flake8-bugbear = "^21.9.1"
-mkdocs-material = "^7.2.6"
+mkdocs-material = "^7.2.8"
 mkdocs-git-revision-date-plugin = "^0.3.1"
 mike = "^0.6.0"
 mypy = "^0.910"