Fix missing memoization in Web::PushNotificationWorker (#36085)

app/workers/web/push_notification_worker.rb

@@ -96,7 +96,7 @@ class Web::PushNotificationWorker
   end
 
   def web_push_request
-    @web_push_request || WebPushRequest.new(@subscription)
+    @web_push_request ||= WebPushRequest.new(@subscription)
   end
 
   def push_notification_json