docs: fix usage of AdminCreateProduct in validation of digital produc…

…t recipe

www/apps/resources/app/recipes/digital-products/examples/standard/page.mdx

@@ -686,7 +686,7 @@ export const createDigitalProductsSchema = z.object({
     file_id: z.string(),
     mime_type: z.string(),
   })),
-  product: AdminCreateProduct,
+  product: AdminCreateProduct(),
 })
 ```
 
@@ -2616,4 +2616,4 @@ Aside from customizing the Next.js Starter storefront, you can also create a cus
 
 ### Admin Development
 
-In this recipe, you learned how to customize the admin with UI routes. You can also do further customization using widgets. Learn more in [this documentation](!docs!/advanced-development/admin).
+In this recipe, you learned how to customize the admin with UI routes. You can also do further customization using widgets. Learn more in [this documentation](!docs!/advanced-development/admin).