remove obsolete permissions block

we use the JF_BOT_TOKEN PAT and not the default GITHUB_TOKEN

.github/workflows/repo-stale.yaml

@@ -5,10 +5,6 @@ on:
     - cron: '30 1 * * *'
   workflow_dispatch:
 
-permissions:
-  issues: write
-  pull-requests: write
-
 jobs:
   stale:
     runs-on: ubuntu-latest