Bump mkdocs from 1.5.2 to 1.5.3 in /docs (#98)

Bumps [mkdocs](https://github.com/mkdocs/mkdocs) from 1.5.2 to 1.5.3.
- [Release notes](https://github.com/mkdocs/mkdocs/releases)
- [Commits](mkdocs/mkdocs@1.5.2...1.5.3)

---
updated-dependencies:
- dependency-name: mkdocs
  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>

docs/requirements.txt

@@ -1,4 +1,4 @@
-mkdocs==1.5.2
+mkdocs==1.5.3
 mkdocs-material==9.2.5
 mkdocs-git-revision-date-localized-plugin==1.2.0
 mkdocs-glightbox==0.3.4