Declare permissions

Repositories can be configured with Default access (restricted)
https://docs.github.com/en/actions/security-guides/automatic-token-authentication#permissions-for-the-github_token

Best practice says that workflows should declare the minimal permissions they require.
Without declaring permissions, paranoid forks fail miserably.

.github/workflows/check-change-note.yml

@@ -1,5 +1,8 @@
 name: Check change note
 
+permissions:
+  pull-requests: read
+
 on:
   pull_request_target:
     types: [labeled, unlabeled, opened, synchronize, reopened, ready_for_review]