fix: frontend build runs on push

Author: gregory-j-baker

.github/workflows/build-frontend.yaml

@@ -1,6 +1,12 @@
 name: Build Future SIR frontend
 
 on:
+  push:
+    branches:
+      - main
+    paths:
+      - .github/workflows/build-frontend.yaml
+      - frontend/**
   workflow_call: {}
   workflow_dispatch: {}
 
@@ -24,4 +30,4 @@ jobs:
       - run: npm run test:e2e
         working-directory: frontend
       - run: podman build --file containerfile .
-        working-directory: frontend
+        working-directory: frontend