build(deps): Bump actions/cache from 2.1.5 to 2.1.6

Bumps [actions/cache](https://github.com/actions/cache) from 2.1.5 to 2.1.6.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](https://github.com/actions/cache/compare/v2.1.5...v2.1.6)

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

.github/workflows/security-analysis.yml

@@ -30,7 +30,7 @@ jobs:
 
       - name: Cache Docker layers
         if: github.event_name != 'schedule'
-        uses: actions/cache@v2.1.5
+        uses: actions/cache@v2.1.6
         with:
           path: ${{ env.CACHE_PATH }}
           key: ${{ runner.os }}-buildx-${{ github.sha }}