Comment the reason for disable the check

.github/workflows/ci.yml

@@ -159,6 +159,7 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       contents: write
+    # Only run on the main repository because forks do not have write access to the main repository.
     if: github.event.pull_request.head.repo.fork == false
     steps:
     - uses: actions/checkout@v4