Add contents: read permission to AI Moderator workflow

Co-authored-by: stnguyen90 <1477010+stnguyen90@users.noreply.github.com>

.github/workflows/ai-moderator.yml

@@ -17,6 +17,7 @@ on:
     types: [created, edited]
 
 permissions:
+  contents: read
   issues: write
   pull-requests: write
   discussions: write