enable cache for docker layers

.github/workflows/docker-images.yml

@@ -60,6 +60,15 @@ jobs:
       -
         name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
+      -
+        name: Cache Docker layers
+        uses: actions/cache@v2
+        with:
+          path: /tmp/.buildx-cache
+          key: ${{ runner.os }}-buildx-${{ matrix.image }}-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-buildx-${{ matrix.image }}-
+            ${{ runner.os }}-buildx-
       -
         name: Login to DockerHub
         uses: docker/login-action@v1 
@@ -75,3 +84,5 @@ jobs:
           platforms: linux/amd64,linux/arm64
           push: true
           tags: tunathu/${{ matrix.image }}:${{ env.docker_tag }}
+          cache-from: type=local,src=/tmp/.buildx-cache
+          cache-to: type=local,dest=/tmp/.buildx-cache