Bump sphinx from 3.4.0 to 4.3.2 (#192)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 3.4.0 to 4.3.2.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/4.x/CHANGES)
- [Commits](sphinx-doc/sphinx@v3.4.0...v4.3.2)

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

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