Fix devcontainer setup

examples/fullstack/backend/start/routes.ts

@@ -8,10 +8,10 @@
 */
 
 import router from '@adonisjs/core/services/router'
-import UsersController from '#controllers/users_controller'
+const UsersController = () => import('#controllers/users_controller')
 router.get('users', [UsersController, 'index'])
 router.get('/', async () => {
   return {
-    hello: 'world',
+    hello: 'WORLD',
   }
 })