Error deploying azure-quickstart-templates/rds-deployment-existing-ad

[rds-deployment-existing-ad](https://github.com/Azure/azure-quickstart-templates/tree/master/rds-deployment-existing-ad)

### Issue Details

Hi, I'm attempting to deploy this template on Azure using an existing Azure Active Directory Domain Service. It fails at cb-vm\rdsdeployment. It appears to be an account issue, but it was successful at joining the domain. Has anyone had success with AADDS instead of using a AD domain controller?

Thanks.

{
"status": "Failed",
"error": {
"code": "ResourceDeploymentFailure",
"message": "The resource operation completed with terminal provisioning state 'Failed'.",
"details": [
{
"code": "VMExtensionProvisioningError",
"message": "VM has reported a failure when processing extension 'rdsdeployment'. Error message: \"DSC Configuration 'RDSDeployment' completed with error(s). Following are the first few: Logon failure: the user has not been granted the requested logon type at this computer The SendConfigurationApply function did not succeed. LCM failed to start desired state configuration manually.\"."

from the security event log on broker vm:

Log Name: Security
Source: Microsoft-Windows-Security-Auditing
Date: 8/17/2018 6:47:05 PM
Event ID: 4625
Task Category: Logon
Level: Information
Keywords: Audit Failure
User: N/A
Computer: broker.xxx.onmicrosoft.com
Description:
An account failed to log on.

Subject:
Security ID: SYSTEM
Account Name: broker$
Account Domain: xxx
Logon ID: 0x3E7

Logon Type: 4

Account For Which Logon Failed:
Security ID: NULL SID
Account Name: sa
Account Domain: xxx

Failure Information:
Failure Reason: The user has not been granted the requested logon type at this machine.
Status: 0xC000015B
Sub Status: 0x0

Start with the rds-deployment-existing-ad template and the cb-vm\rdsdeployment extension referenced in the report. Review the deployment failure and broker Security event 4625 to determine whether Azure Active Directory Domain Services is supported by this template. Done means the template's AADDS compatibility is established and the deployment either succeeds or documents the required limitation or change.

Written by the indexing model from the issue text.