Bump sphinx from 8.2.3 to 9.0.4 in /docs

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 8.2.3 to 9.0.4.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/v9.0.4/CHANGES.rst)
- [Commits](sphinx-doc/sphinx@v8.2.3...v9.0.4)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-version: 9.0.4
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

docs/requirements.txt

@@ -39,7 +39,7 @@ ruamel.yaml.clib==0.2.15
 six==1.17.0
 snowballstemmer==3.0.1
 soupsieve==2.8
-Sphinx==8.2.3
+Sphinx==9.0.4
 sphinx-autodoc-typehints==3.5.2
 sphinx-basic-ng==1.0.0b2
 sphinx-jinja2-compat==0.4.1