Replace buildx cache with standard registry

This is more consistent with the other repos and allows more caching
options

.github/workflows/build.yml

@@ -27,17 +27,8 @@ jobs:
           password: ${{ secrets.DOCKERHUB_PASSWORD }}
 
       - name: Set up Docker Buildx
-        id: buildx
         uses: docker/setup-buildx-action@v1
 
-      - name: Cache Docker layers
-        uses: actions/cache@v2.1.6
-        with:
-          path: /tmp/.buildx-cache
-          key: ${{ runner.os }}-buildx-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-buildx-
-
       - name: Set Environment Variables (Push)
         if: github.event_name == 'push'
         run: |
@@ -56,6 +47,21 @@ jobs:
           # This is the latest commit on the actual PR branch
           echo "DOCKER_IMAGE_TAG=${{ github.event.pull_request.head.sha }}" >> $GITHUB_ENV
 
+      - name: Build Docker Image - base-image target
+        uses: docker/build-push-action@v2
+        with:
+          tags: |
+            ${{ env.DOCKER_IMAGE}}:base-image-${{ env.BRANCH_TAG }}
+          push: ${{ github.actor != 'dependabot[bot]' }}
+          load: ${{ github.actor == 'dependabot[bot]' }}
+          target: base-image
+          cache-from: |
+            ${{ env.DOCKER_IMAGE}}:base-image-${{ env.BRANCH_TAG }}
+            ${{ env.DOCKER_IMAGE}}:base-image-master
+          build-args: |
+            BUILDKIT_INLINE_CACHE=1
+            COMMIT_SHA=${{ env.DOCKER_IMAGE_TAG}}
+
       - name: Build Docker Image
         uses: docker/build-push-action@v2
         with:
@@ -64,10 +70,13 @@ jobs:
             ${{ env.DOCKER_IMAGE}}:${{ env.BRANCH_TAG }}
           push: ${{ github.actor != 'dependabot[bot]' }}
           load: ${{ github.actor == 'dependabot[bot]' }}
-          builder: ${{ steps.buildx.outputs.name }}
-          cache-to:   type=local,dest=/tmp/.buildx-cache
-          cache-from: type=local,src=/tmp/.buildx-cache
-          build-args: COMMIT_SHA=${{ env.DOCKER_IMAGE_TAG}}
+          cache-from: |
+            ${{ env.DOCKER_IMAGE}}:${{ env.BRANCH_TAG }}
+            ${{ env.DOCKER_IMAGE}}:master
+            ${{ env.DOCKER_IMAGE}}:base-image-${{ env.BRANCH_TAG }}
+          build-args: |
+            BUILDKIT_INLINE_CACHE=1
+            COMMIT_SHA=${{ env.DOCKER_IMAGE_TAG}}
 
       - name: Pull image if not loaded
         if: ${{ github.actor != 'dependabot[bot]' }}