Bump sphinx from 7.3.5 to 7.3.6 in /docs

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 7.3.5 to 7.3.6.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v7.3.5...v7.3.6)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

docs/requirements.txt

@@ -15,7 +15,7 @@ requests>=2.20.0
 setuptools==69.5.1
 six==1.16.0
 snowballstemmer==2.2.0
-sphinx==7.3.5
+sphinx==7.3.6
 sphinxcontrib-websupport==1.2.7
 typing==3.7.4.3
 urllib3>=1.24.2