ci: Downgrage labeler back to v4

Author: jcs090218

.github/workflows/labeler.yml

@@ -6,7 +6,7 @@ jobs:
   triage:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/labeler@v6
+    - uses: actions/labeler@v4
       with:
         repo-token: "${{ secrets.GITHUB_TOKEN }}"
         sync-labels: true