ci, img build: build the controller image

Signed-off-by: Miguel Duarte Barroso <[email protected]>

.github/workflows/image-build.yaml

@@ -0,0 +1,20 @@
+name: Image build
+on: [pull_request]
+jobs:
+  build-amd64:
+    name: Image build/amd64
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Build container image
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          push: false
+          tags: ghcr.io/${{ github.repository }}:latest-amd64
+          file: Dockerfile