Bump actions/cache from 1 to 2.1.6 (#5252)

Bumps [actions/cache](https://github.com/actions/cache) from 1 to 2.1.6. - [Release notes](https://github.com/actions/cache/releases) - [Commits](https://github.com/actions/cache/compare/v1...v2.1.6) --- updated-dependencies: - dependency-name: actions/cache dependency-type: direct:production update-type: version-update:semver-major ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bump actions/cache from 1 to 2.1.6 (#5252)
aa265041 · dependabot[bot] · GitHub · fb12faaf · aa265041
--- a/.github/workflows/ci-testing.yml
+++ b/.github/workflows/ci-testing.yml
@@ -39,7 +39,7 @@ jobs:
          python -c "from pip._internal.locations import USER_CACHE_DIR; print('::set-output name=dir::' + USER_CACHE_DIR)"

      - name: Cache pip
-        uses: actions/cache@v1
+        uses: actions/cache@v2.1.6
        with:
          path: ${{ steps.pip-cache.outputs.dir }}
          key: ${{ runner.os }}-${{ matrix.python-version }}-pip-${{ hashFiles('requirements.txt') }}