Bump mypy from 0.930 to 0.931 (#19)

Bumps [mypy](https://github.com/python/mypy) from 0.930 to 0.931.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.930...v0.931)

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

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

Author: dependabot[bot]

requirements-dev.txt

@@ -1,4 +1,4 @@
 coverage[toml]==6.2
 flake8==4.0.1
-mypy==0.930
+mypy==0.931
 pyperf==2.3.0