build(deps): bump actions/cache from 2 to 2.1.5 (#870)

.github/workflows/build-multiarch.yml

@@ -46,7 +46,7 @@ jobs:
         uses: docker/setup-buildx-action@v1
 
       - name: Cache Docker layers
-        uses: actions/cache@v2
+        uses: actions/cache@v2.1.5
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ steps.prep.outputs.cache_version }}-${{ github.sha }}

.github/workflows/main.yml

@@ -59,7 +59,7 @@ jobs:
       uses: docker/setup-buildx-action@v1
 
     - name: Cache Docker layers
-      uses: actions/cache@v2
+      uses: actions/cache@v2.1.5
       with:
         path: /tmp/.buildx-cache
         key: ${{ runner.os }}-buildx-${{ steps.prep.outputs.cache_version }}-${{ github.sha }}