Bump sphinx from 4.5.0 to 5.1.1

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 4.5.0 to 5.1.1.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/5.x/CHANGES)
- [Commits](sphinx-doc/sphinx@v4.5.0...v5.1.1)

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

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

Author: dependabot[bot]

setup.py

@@ -46,7 +46,7 @@
             "recommonmark==0.7.1",
             "sphinx-autobuild==2021.3.14",
             "sphinx-rtd-theme==1.0.0",
-            "Sphinx==4.5.0",
+            "Sphinx==5.1.1",
         ],
     },
 )