Purview Roles are Set in Purview not Azure Portal

Updated link about setting roles for the Service Principal to point to the deep link on setting the role in the Purview portal.

Author: wjohnson

articles/purview/tutorial-using-rest-apis.md

@@ -69,7 +69,7 @@ Once the new service principal is created, you need to assign the data plane rol
 
 1. Select the **Role assignments** tab.
 
-1. Assign the following roles to the service principal created previously to access various data planes in Microsoft Purview. For detailed steps, see [Assign Azure roles using the Azure portal](../role-based-access-control/role-assignments-portal.md).
+1. Assign the following roles to the service principal created previously to access various data planes in Microsoft Purview. For detailed steps, see [Assign Azure roles using the Microsoft Purview portal](./how-to-create-and-manage-collections.md#add-role-assignments).
 
     * Data Curator role to access Catalog Data plane.
     * Data Source Administrator role to access Scanning Data plane.