Bump actions/cache from 3.2.4 to 3.2.6

Bumps [actions/cache](https://github.com/actions/cache) from 3.2.4 to 3.2.6.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](627f0f41f6...69d9d449ac)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

.github/workflows/tests.yaml

@@ -49,7 +49,7 @@ jobs:
           pip install -U setuptools
           python -m pip install -U pip
       - name: cache mypy
-        uses: actions/cache@627f0f41f6904a5b1efbaed9f96d9eb58e92e920
+        uses: actions/cache@69d9d449aced6a2ede0bc19182fadc3a0a42d2b0
         with:
           path: ./.mypy_cache
           key: mypy|${{ matrix.python }}|${{ hashFiles('pyproject.toml') }}