Bump mkdocs-material from 9.5.26 to 9.6.9 (#243)

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 9.5.26 to 9.6.9.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG)
- [Commits](squidfunk/mkdocs-material@9.5.26...9.6.9)

---
updated-dependencies:
- dependency-name: mkdocs-material
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements-docs.txt

@@ -1,5 +1,5 @@
 mkdocs==1.5.3
-mkdocs-material==9.5.26
+mkdocs-material==9.6.9
 pymdown-extensions==10.7.1
 mike==2.0.0
 mkdocs-simple-hooks==0.1.5