fix: @strapi/design-system does not provide an export named 'Page' (#32)

Co-authored-by: Jamie Howard <48524071+jhoward1994@users.noreply.github.com>

src/cli/commands/plugin/init/files/admin.ts

@@ -11,7 +11,7 @@ export { PluginIcon };
 `;
 
 const APP_CODE = outdent`
-import { Page } from '@strapi/design-system';
+import { Page } from '@strapi/strapi/admin';
 import { Routes, Route } from 'react-router-dom';
 
 import { HomePage } from './HomePage';