[Backport 8.7] Upgrade backport workflow to v2 (#1885)

Co-authored-by: Josh Mock <[email protected]>

Author: github-actions[bot]

.github/workflows/backport.yml

@@ -11,6 +11,6 @@ jobs:
     name: Backport
     steps:
       - name: Backport
-        uses: tibdex/backport@v1
+        uses: tibdex/backport@v2
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}