chore: added build controller ci

Author: paulobressan

.github/workflows/controller.yml

@@ -0,0 +1,40 @@
+name: Controller
+
+on:
+  push:
+    branches:
+      - "main"
+    paths:
+      - ".github/workflows/controller.yml"
+      - "operator/**"
+      
+jobs:
+  build-images:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - context: operator
+            file: operator/Dockerfile
+            endpoint: demeter-run/ext-cardano-dbsync-serverless
+
+    continue-on-error: true
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/[email protected]
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: ${{ matrix.context }}
+          file: ${{ matrix.file }}
+          platforms: linux/amd64
+          push: true
+          tags: ghcr.io/${{ matrix.endpoint }},ghcr.io/${{ matrix.endpoint }}:${{ github.sha }}