Merge branch '218559-add-comment-to-WebHookWorker-about-why-it-is-not-idempotent' into 'master'

Add a comment about why WebHookWorker cannot be idempotent

See merge request gitlab-org/gitlab!60683

app/workers/web_hook_worker.rb

 # frozen_string_literal: true
 
-class WebHookWorker # rubocop:disable Scalability/IdempotentWorker
+# Worker cannot be idempotent: https://gitlab.com/gitlab-org/gitlab/-/issues/218559
+# rubocop:disable Scalability/IdempotentWorker
+class WebHookWorker
   include ApplicationWorker
 
   feature_category :integrations
@@ -16,3 +18,4 @@ class WebHookWorker # rubocop:disable Scalability/IdempotentWorker
     WebHookService.new(hook, data, hook_name).execute
   end
 end
+# rubocop:enable Scalability/IdempotentWorker