Update SQL IaaS Agent extension support details (#36676)

Author: PhilB-MSFT

azure-sql/virtual-machines/windows/media/sql-server-iaas-agent-extension-automate-management/azure-rm-sql-server-iaas-agent-portal.png

@@ -48,6 +48,7 @@ To register your SQL Server VM with the extension, you'll need the following:
 - The latest version of [Azure CLI](/cli/azure/install-azure-cli) or [Azure PowerShell (5.0 minimum)](/powershell/azure/install-az-ps).
 - A minimum of .NET Framework 4.5.1 or later.
 - To verify that none of the [limitations](sql-server-iaas-agent-extension-automate-management.md#limitations) apply to you.
+- A [supported region](sql-server-iaas-agent-extension-automate-management.md#supported-regions) for the SQL IaaS Agent extension.
 
 ## Register subscription with RP