Change token permissions

Change github token permissions in the github action.

Author: amielcza

.github/workflows/stale.yml

@@ -12,6 +12,11 @@ on:
     - cron: '30 1 * * *'  # run every day
   workflow_dispatch: {}
 
+permissions:
+  contents: write
+  issues: write
+  pull-requests: write
+
 jobs:
   stale:
     runs-on: [self-hosted, Linux]