⬆️ Update mypy requirement from ^0.910 to ^0.942

Updates the requirements on [mypy](https://github.com/python/mypy) to permit the latest version.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.910...v0.942)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:development
...

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

pyproject.toml

@@ -52,7 +52,7 @@ pytest = "~=6.0"
 isort = "~=5.8.0"
 black = { version = "*", allow-prereleases = true }
 flake8 = "~=3.9.0"
-mypy = "^0.910"
+mypy = "^0.942"
 coverage = { extras = ["toml"], version = "^5.3" }
 pytest-xdist = "^2.1.0"
 pytz = "^2021.1"