Add react-native as platform (#6663)

Author: timngyn

src/pages/[platform]/build-a-backend/auth/auth-migration-guide/index.mdx

@@ -3,7 +3,7 @@ import { getCustomStaticPath } from '@/utils/getCustomStaticPath';
 export const meta = {
   title: 'Migrate from v5 to v6',
   description: 'Learn more about the migration steps to upgrade Auth APIs for Amplify JavaScript v5 to v6',
-  platforms: ['angular', 'javascript', 'nextjs', 'react', 'vue']
+  platforms: ['angular', 'javascript', 'nextjs', 'react', 'vue', 'react-native']
 };
 
 export const getStaticPaths = async () => {