Update stale.yml (#45902)

.github/workflows/stale.yml

@@ -17,8 +17,8 @@ jobs:
           days-before-stale: 30
           # We don't want any Issues to be marked as stale for now.
           days-before-issue-stale: -1
-          exempt-issue-label: no stalebot
-          exempt-pr-label: no stalebot
+          exempt-issue-labels: no stalebot
+          exempt-pr-labels: no stalebot
           stale-issue-label: stale
           stale-pr-label: stale
           stale-pr-message: >