Update mirror.yml to run at low loads time

https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#schedule

.github/workflows/mirror.yml

@@ -5,7 +5,7 @@ on:
     branches:
         - __mirror
   schedule:
-    - cron: '* 3 * * *'
+    - cron: '47 11 * * *'
   workflow_dispatch:
 
 jobs: