Update how-to-managed-network.md

add note about UAI workspace

Author: meerakurup

articles/machine-learning/how-to-managed-network.md

@@ -153,6 +153,9 @@ Before following the steps in this article, make sure you have the following pre
 
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+> [!NOTE]
+> If you are using UAI workspace please make sure to add the Network Contributor role to your identity. For more information, see [User-assigned managed identity](how-to-identity-based-service-authentication.md).
+
 ## Configure a managed virtual network to allow internet outbound
 
 > [!TIP]