ci: add GitHub token permissions for workflow (#24332)

Signed-off-by: Varun Sharma <varunsh@stepsecurity.io>

.github/workflows/ci.yml

@@ -12,6 +12,9 @@ on:
       - 'docs/**'
       - 'files/**'
 
+permissions:
+  contents: read
+
 jobs:
 
   lint: