fix(docs): Fixed the code example for the Permissions - Frontend Integration

The current default code is exactly what it is in this example, except for the flawed import.

Signed-off-by: Valentin Grégoire <32612304+valentingregoire@users.noreply.github.com>

docs/permissions/frontend-integration.md

@@ -13,16 +13,11 @@ However, there are some cases where the integrator needs to supplement the polic
 If your Backstage permission policy may return a `DENY` for users requesting the `catalogEntityCreatePermission`, it may make sense, for example, to remove access to the `/catalog-import` page entirely:
 
 ```tsx title="packages/app/src/App.tsx"
-/* highlight-add-start */
 import { RequirePermission } from '@backstage/plugin-permission-react';
-import { catalogEntityCreatePermission } from '@backstage/plugin-catalog-common';
-/* highlight-add-end */
+import { catalogEntityCreatePermission } from '@backstage/plugin-catalog-common/alpha';
 
 const routes = (
   <FlatRoutes>
-    {/* highlight-remove-next-line */}
-    <Route path="/catalog-import" element={<CatalogImportPage />} />
-    {/* highlight-add-start */}
     <Route
       path="/catalog-import"
       element={
@@ -31,7 +26,6 @@ const routes = (
         </RequirePermission>
       }
     />
-    {/* highlight-add-end */}
     {/* ... */}
   </FlatRoutes>
 );