Update articles/machine-learning/how-to-identity-based-service-authentication.md

Co-authored-by: SeokJin Han <[email protected]>

Author: deeikele

articles/machine-learning/how-to-identity-based-service-authentication.md

@@ -51,7 +51,7 @@ The following [Azure RBAC role assignments](../role-based-access-control/role-as
 
 |Resource|Permission|
 |---|---|
-|Azure Storage|Contributor + optional Storage Blob Data Contributor to enable data preview in the Azure Machine Learning studio|
+|Azure Storage|Contributor (control plane) + Storage Blob Data Contributor (data plane, optional, to enable data preview in the Azure Machine Learning studio)|
 |Azure Key Vault (when using [RBAC permission model](../key-vault/general/rbac-guide.md))|Contributor (control plane) + Key Vault Administrator (data plane)|
 |Azure Key Vault (when using [access policies permission model](../key-vault/general/assign-access-policy.md))|Contributor + any access policy permissions besides **purge** operations|
 |Azure Container Registry|Contributor|