Bump mypy from 0.942 to 0.950 (#5630)

Bumps [mypy](https://github.com/python/mypy) from 0.942 to 0.950.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.942...v0.950)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

dev-requirements.txt

@@ -4,7 +4,7 @@
 flake8
 
 # Static type checking
-mypy==0.942
+mypy==0.950
 
 # Automatic code formatting
 black==22.3.0