update CI workflow

.github/workflows/build-and-release.yaml

@@ -57,7 +57,7 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      # Build and push Docker image with Buildx (don't push on PR)
+      # Build and push Docker image with Buildx
       # https://github.com/docker/build-push-action
       - name: Build and push Docker image
         id: build-and-push

.github/workflows/ci.yml

@@ -2,17 +2,29 @@ name: CI
 
 on:
   push:
-    branches: [ "main" ]
+    branches-ignore: [ "main" ]
   pull_request:
-    branches: [ "main" ]
+    branches-ignore: [ "main" ]
 
 jobs:
 
   build:
-
     runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v3
-    - name: Build the Docker image
-      run: docker build . --file Dockerfile --tag shipped:$(date +%s)
+
+      # Set up BuildKit Docker container builder to be able to build
+      # multi-platform images and export cache
+      # https://github.com/docker/setup-buildx-action
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@f95db51fddba0c2d1ec667646a06c2ce06100226 # v3.0.0
+
+    - name: Build Docker image
+      id: build
+      uses: docker/build-push-action@0565240e2d4ab88bba5387d719585280857ece09 # v5.0.0
+      with:
+        context: .
+        push: false
+        cache-from: type=gha
+        cache-to: type=gha,mode=max