Add a github issue label to shoo the stalebot away (#42950)

Labeling an issue with "never stale" will keep the stalebot away; the
bot can get annoying in some situations otherwise.

Release Notes:

- N/A

.github/workflows/community_close_stale_issues.yml

@@ -26,3 +26,4 @@ jobs:
           ascending: true
           enable-statistics: true
           stale-issue-label: "stale"
+          exempt-issue-labels: "never stale"