Add contents: write (#36445)

fix permission

Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

.github/workflows/change_pr_to_draft.yml

@@ -10,6 +10,7 @@ jobs:
     name: Convert PR to draft
     permissions:
       pull-requests: write
+      contents: write
     if: github.event.pull_request.draft == false
     steps:
       - name: Convert PR to draft