Bump mypy from 0.931 to 0.941 (#639)

Bumps [mypy](https://github.com/python/mypy) from 0.931 to 0.941.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.931...v0.941)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:production
  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>

test-requirements.txt

@@ -4,7 +4,7 @@ pycodestyle==2.8.0
 pydocstyle==6.0.0
 dodgy==0.2.1
 isort==5.10.1
-mypy==0.931
+mypy==0.941
 Werkzeug==1.0.1
 Flask-Testing==0.8.1
 blinker==1.4