Possible fix for broken GitHub Action.

Author: iamalexrouse

.github/workflows/pull_request_opened.yml

@@ -22,5 +22,8 @@ jobs:
         sync-labels: true
   assign-author:
     runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+      
     steps:
       - uses: toshimaru/auto-author-assign@v2.1.1