fix(deps): bump actions/cache from 2.1.4 to 2.1.6

Bumps [actions/cache](https://github.com/actions/cache) from 2.1.4 to 2.1.6.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](actions/cache@v2.1.4...v2.1.6)

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
           node-version: ${{ matrix.node }}
 
       - name: Cache node_modules 📦
-        uses: actions/cache@v2.1.4
+        uses: actions/cache@v2.1.6
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}