Bump mkdocstrings from 0.19.1 to 0.20.0 (#470)

Bumps [mkdocstrings](https://github.com/mkdocstrings/mkdocstrings) from 0.19.1 to 0.20.0.
- [Release notes](https://github.com/mkdocstrings/mkdocstrings/releases)
- [Changelog](https://github.com/mkdocstrings/mkdocstrings/blob/master/CHANGELOG.md)
- [Commits](mkdocstrings/mkdocstrings@0.19.1...0.20.0)

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

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

requirements.txt

@@ -10,7 +10,7 @@ mkdocs-macros-plugin==0.7.0
 mkdocs-material==9.0.12
 mkdocs==1.4.2
 mkdocstrings-python-legacy==0.2.3
-mkdocstrings==0.19.1
+mkdocstrings==0.20.0
 pillow==9.4.0
 pip-upgrader==1.4.15
 pydocstyle==6.3.0