Build only on version tags

.github/workflows/docker.yml

@@ -1,6 +1,9 @@
 name: Build Docker images
 
-on: ["push"]
+on:
+  push:
+    tags:
+      - 'v*.*.*'
 
 jobs:
   docker:
@@ -27,14 +30,12 @@ jobs:
         with:
           images: |
             ghcr.io/${{ matrix.image }}
-          # generate Docker tags based on the following events/attributes
           tags: |
-            type=ref,event=branch
+            type=ref,event=tag
+            type=semver,pattern={{version}}
             type=sha
-            latest
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
-      # So now you can use Actions' own caching!
       - name: Log in to the Container registry
         uses: docker/login-action@v1
         with:
@@ -49,3 +50,4 @@ jobs:
           push: true
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
+          platforms: linux/amd64,linux/arm64  # Specify platforms here.