update auto-update PR wf

Author: GitHub Copilot

.github/workflows/auto-update-pr-branches.yaml

@@ -38,9 +38,14 @@ jobs:
               # Jeeves from re-approving and re-enabling auto-merge on that PR.
               merge_state=$(gh pr view "$pr" --repo "${{ github.repository }}" \
                 --json mergeStateStatus --jq '.mergeStateStatus' 2>/dev/null || echo "ERROR")
+              
               if [ "$merge_state" = "BEHIND" ]; then
                 echo "PR #$pr is behind main, triggering Dependabot rebase"
                 gh pr comment --repo "${{ github.repository }}" "$pr" --body "@dependabot rebase" || true
+              else
+              if [ "$merge_state" = "UNKNOWN" ]; then
+                echo "PR #$pr state UNKNOWN, triggering Dependabot rebase anyway to be safe"
+                gh pr comment --repo "${{ github.repository }}" "$pr" --body "@dependabot rebase" || true
               else
                 echo "PR #$pr merge state is '$merge_state', no update needed"
               fi