Fix operator build push job

.github/workflows/serverless-operator-build-push.yaml

@@ -1,8 +1,8 @@
-name: serverless operator build (pull)
+name: serverless operator build (push)
 
 on:
-  pull_request_target:
-    types: [opened, edited, synchronize, reopened, ready_for_review]
+  push:
+    branches: [ "main", "release-*" ]
 
 permissions:
   id-token: write
@@ -19,10 +19,7 @@ jobs:
 
       - name: Get the latest tag
         id: get_tag
-        run: echo ::set-output name=TAG::PR-${{ github.event.pull_request.number }}
-
-      - name: Echo the tag
-        run: echo ${{ steps.get_tag.outputs.TAG }}
+        run: echo ::set-output name=TAG::${{ github.sha }}}
 
   build-image:
     needs: compute-tag
@@ -32,10 +29,3 @@ jobs:
       dockerfile: components/operator/Dockerfile
       context: .
       tags: ${{ needs.compute-tag.outputs.tag }}
-
-  test-image:
-    runs-on: ubuntu-latest
-    needs: build-image
-    steps:
-      - name: Test image
-        run: echo "Testing image ${{ needs.build-image.outputs.images }}"