build(deps): bump actions/cache from 2.1.6 to 2.1.7

Bumps [actions/cache](https://github.com/actions/cache) from 2.1.6 to 2.1.7.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](actions/cache@v2.1.6...v2.1.7)

---
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/ci.yml

@@ -49,7 +49,7 @@ jobs:
         run: "python3 -m pip install poetry==${{ env.POETRY_VERSION }}"
 
       - name: "Cache venv"
-        uses: "actions/cache@v2.1.6"
+        uses: "actions/cache@v2.1.7"
         with:
           path: "./.venv/"
           key: "venv-${{ matrix.python-version }}-${{ hashFiles('poetry.lock') }}"
@@ -105,7 +105,7 @@ jobs:
         run: "python3 -m pip install poetry==${{ env.POETRY_VERSION }} tox==${{ env.TOX_VERSION }} tox-gh-actions==${{ env.TOX_GH_ACTIONS_VERSION }}"
 
       - name: "Cache venv"
-        uses: "actions/cache@v2.1.6"
+        uses: "actions/cache@v2.1.7"
         with:
           path: "./.venv/"
           key: "venv-${{ matrix.python-version }}-${{ hashFiles('poetry.lock') }}"