Bump mkdocs-material from 7.1.4 to 7.1.8 (fastapiutils#64)

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 7.1.4 to 7.1.8.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/docs/changelog.md)
- [Commits](squidfunk/mkdocs-material@7.1.4...7.1.8)

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

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