Build container on PR (but don't publish) to verify Containerfile syntax

Author: AshCorr

.github/workflows/pull_requests.yml

@@ -33,6 +33,15 @@ jobs:
       if: success()
       run: npx grunt prod
 
+    - name: Production Image Build
+      if: success()
+      id: build-image
+      uses: redhat-actions/buildah-build@v2
+      with:
+        containerfiles: ./Containerfile
+        platforms: linux/arm64, linux/amd64
+        oci: true
+
     - name: UI Tests
       if: success()
       run: |