ci: declare contents:read on sync-ruby workflow

Signed-off-by: Arpit Jain <arpitjain099@gmail.com>

Author: arpitjain099

.github/workflows/sync-ruby.yml

@@ -2,6 +2,9 @@ name: Sync ruby
 on:
   push:
     branches: [master]
+permissions:
+  contents: read
+
 jobs:
   sync:
     name: Sync ruby