Bump sphinx from 5.3.0 to 7.1.1

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 5.3.0 to 7.1.1.
- [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...v7.1.1)

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

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

setup.py

@@ -78,7 +78,7 @@
             "mypy==v0.971 ; python_version>='3.6' and python_version<'3.7'",
             "mypy==v1.4.1 ; python_version>='3.7'",
             # Docs.
-            "Sphinx==5.3.0 ; python_version>='3.8'",
+            "Sphinx==7.1.1 ; python_version>='3.8'",
             "sphinx-autobuild==2021.3.14 ; python_version>='3.8'",
             "sphinx-rtd-theme==1.2.0 ; python_version>='3.8'",
         ]