Bump sphinx from 4.0.2 to 4.1.1 (#601)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 4.0.2 to 4.1.1.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/4.x/CHANGES)
- [Commits](sphinx-doc/sphinx@v4.0.2...v4.1.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

requirements/doc.txt

@@ -1,4 +1,4 @@
-sphinx==4.0.2
+sphinx==4.1.1
 sphinxcontrib-asyncio==0.3.0
 alabaster==0.7.12
 sphinx-autodoc-typehints==1.12.0