Add permissions for pull-requests in stale workflow

Added permissions for pull-requests to allow commenting and labeling.

Author: taladrane

.github/workflows/stale.yaml

@@ -4,6 +4,9 @@ on:
   schedule:
   - cron: "00 0 * * *" # runs at 00:00 daily
 
+permissions:
+  pull-requests: write   # Required to comment on, label, and close PRs
+
 jobs:
   stale: