docker: updating action to run for correctly capturing BUILDPLATFORM …

…value

.github/workflows/docker-release.yml

@@ -35,13 +35,11 @@ jobs:
         restore-keys: |
           ${{ runner.os }}-buildx-
 
-    - name: Build and push Docker image
-      uses: docker/build-push-action@v2
-      with:
-        context: .
-        push: true
-        platforms: linux/arm64,linux/arm/v7
-        tags: |
-          elementsproject/lightningd:${{ github.event.inputs.version }}
-        cache-from: type=local,src=/tmp/.buildx-cache
-        cache-to: type=local,dest=/tmp/.buildx-cache
+    - name: Build and push Docker images
+      run: |
+        docker buildx build \
+          --platform linux/arm64,linux/arm/v7 \
+          --tag elementsproject/lightningd:${{ github.event.inputs.version }} \
+          --cache-from type=local,src=/tmp/.buildx-cache \
+          --cache-to type=local,dest=/tmp/.buildx-cache \
+          --push .