Bump actions/cache from v2 to v2.1.4 (#898)

Bumps [actions/cache](https://github.com/actions/cache) from v2 to v2.1.4.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](https://github.com/actions/cache/compare/v2...26968a09c0ea4f3e233fdddbafd1166051a095f6)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci-docker.yaml

@@ -14,7 +14,7 @@ jobs:
         uses: docker/setup-buildx-action@v1
       -
         name: "Cache Docker layers"
-        uses: actions/cache@v2
+        uses: actions/cache@v2.1.4
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ github.sha }}

.github/workflows/ci-test.yaml

@@ -17,7 +17,7 @@ jobs:
         go-version: ${{ matrix.go-version }}
     - name: checkout code
       uses: actions/checkout@v2
-    - uses: actions/cache@v2
+    - uses: actions/cache@v2.1.4
       with:
         path: |
           ~/go/pkg/mod              # Module download cache