Sets the stalebot to 10 AM CEST (#25678)

This sets the stale bot trigger time at 10 AM CEST rather than 5 PM CEST as all core maintainers on watch duty are now in the European timezone

.github/workflows/stale.yml

@@ -2,7 +2,7 @@ name: Stale Bot
 
 on:
   schedule:
-    - cron: "0 15 * * *"
+    - cron: "0 8 * * *"
 
 jobs:
   close_stale_issues: