Fix errors in github action

.github/workflows/backport.yaml

@@ -24,12 +24,16 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.head_ref }}
+          ref: main
           lfs: true
           # We cannot use the default GITHUB_TOKEN as it is restricted and cannot
           # trigger another workflow run, which is needed here to trigger the COPR build
           token: ${{ secrets.COMMIT_TOKEN }}
 
+      # 2.5. Configure Git safe directory
+      - name: Configure Git safe directory
+        run: git config --global --add safe.directory "$GITHUB_WORKSPACE"
+
       # 3. Run the update script in the container
       - name: Run update script
         run: ./update.sh