Bump mkdocs-material from 9.0.5 to 9.0.11 in /docs (#586)

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 9.0.5 to 9.0.11.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG)
- [Commits](squidfunk/mkdocs-material@9.0.5...9.0.11)

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

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