Try to get documentation flow working

.github/workflows/documentation.yml

@@ -1,11 +1,6 @@
 name: Assembly Documentation
 
 on:
-  pull_request:
-    branches:
-      - main
-    types:
-      - closed
   push:
     branches:
       - main
@@ -16,8 +11,8 @@ env:
 
 jobs:
   buildfiles:
-    if: github.event.pull_request.merged == true
     name: Design check & documentation build
+      if: github.event_name == 'pull_request' && github.event.action == 'closed' && github.event.pull_request.merged == true
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code