Checkout repository first

Author: dstansby

.github/workflows/needs_release_notes.yml

@@ -11,6 +11,7 @@ jobs:
       pull-requests: write
     runs-on: ubuntu-latest
     steps:
+    - uses: actions/checkout@v4
     - uses: actions/labeler@8558fd74291d67161a8a78ce36a881fa63b766a9  # v5.0.0
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}