VM configuration failed in 'RDS farm deployment using existing active directory' quick start

[RDS farm deployment using existing active directory](https://github.com/Azure/azure-quickstart-templates/tree/master/application-workloads/rds/rds-deployment-existing-ad)

### Issue Details
Failed to find the Configuration.zip file during deployment.

This
"ModulesUrl": "[uri(parameters('_artifactsLocation'),concat('DSC/Configuration.zip', parameters('_artifactsLocationSasToken')))]"

returns 404 - seems that to get the Raw version of the .zip file, GitHub has changed the URL to be this one:
https://github.com/Azure/azure-quickstart-templates/blob/master/application-workloads/rds/rds-deployment-existing-ad/DSC/Configuration.zip?raw=true

this means that the call 'eployment().properties.templateLink.uri' will no longer work for getting the .zip file

Start in application-workloads/rds/rds-deployment-existing-ad and inspect the template's ModulesUrl reference to DSC/Configuration.zip and deployment().properties.templateLink.uri. Reproduce the quick start deployment and verify that Configuration.zip is retrieved successfully instead of returning 404.

Written by the indexing model from the issue text.