Update MIGRATION-guide-for-next-generation-management-libraries.md (Azure#19398)

* Update MIGRATION-guide-for-next-generation-management-libraries.md

* Update MIGRATION-guide-for-next-generation-management-libraries.md

Author: qiaozha

documentation/MIGRATION-guide-for-next-generation-management-libraries.md

@@ -44,7 +44,7 @@ import { ClientSecretCredential } from "@azure/identity";
 const credentials = new ClientSecretCredential(tenantId, clientId, clientSecrat);
 ```
 
-Refer to [@azure/identity](https://www.npmjs.com/package/@azure/identity) for more details.
+Please refer to [@azure/identity](https://www.npmjs.com/package/@azure/identity) for more details about @azure/identity and [migration guide from @azure/ms-rest-nodeauth to @azure/identity](https://github.com/Azure/ms-rest-nodeauth/blob/master/migrate-to-identity-v2.md) on how to migrate from @azure/ms-rest-nodeauth.  
 
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