Bump mypy from 0.961 to 0.971 (#384)

Bumps [mypy](https://github.com/python/mypy) from 0.961 to 0.971.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.961...v0.971)

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

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

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

Author: dependabot[bot]

mypy_requirements.txt

@@ -1,2 +1,2 @@
 # Requirements to run mypy itself. Mypy executable exists in a separate venv.
-mypy==0.961
+mypy==0.971