Shortened IAM heading

Author: rolyon

articles/role-based-access-control/role-assignments-portal.md

@@ -29,7 +29,7 @@ To add or remove role assignments, you must have:
 
 - `Microsoft.Authorization/roleAssignments/write` and `Microsoft.Authorization/roleAssignments/delete` permissions, such as [User Access Administrator](built-in-roles.md#user-access-administrator) or [Owner](built-in-roles.md#owner)
 
-## Overview of Access control (IAM)
+## Access control (IAM)
 
 **Access control (IAM)** is the blade that you use to assign roles to grant access to Azure resources. It's also known as identity and access management and appears in several locations in the Azure portal. The following shows an example of the Access control (IAM) blade for a subscription.