Bump sphinx from 5.3.0 to 7.2.3 in /docs

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 5.3.0 to 7.2.3.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES)
- [Commits](sphinx-doc/sphinx@v5.3.0...v7.2.3)

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

Signed-off-by: dependabot[bot] <[email protected]>

docs/requirements.txt

@@ -1,5 +1,5 @@
 furo==2022.9.29
-sphinx==5.3.0
+sphinx==7.2.3
 sphinx-click==4.3.0
 myst_parser==0.18.1
 linkify-it-py == 2.0.0