Bump sphinx from 5.3.0 to 6.2.1

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 5.3.0 to 6.2.1.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES)
- [Commits](https://github.com/sphinx-doc/sphinx/compare/v5.3.0...v6.2.1)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

requirements-dev.txt

@@ -7,7 +7,7 @@ splinter==0.19.0
 selenium==4.9.0
 twine==4.0.2
 Pallets-Sphinx-Themes==2.0.3
-Sphinx==5.3.0
+Sphinx==6.2.1
 sphinx-issues==3.0.1
 sphinx-jinja==2.0.2
 sphinx-tabs==3.4.1