only when pushed to main

Author: pfefferle

.github/workflows/wp-phpunit.yml

@@ -1,7 +1,9 @@
 name: WordPress Unit Testing
 on:
-    push:
-    pull_request:
+  push:
+    branches:
+      - main
+  pull_request:
 jobs:
   phpunit:
     runs-on: ubuntu-latest