201-vm-sql-full-autobackup - invalid powershell script

[201-vm-sql-full-autobackup](https://github.com/Azure/azure-quickstart-templates/tree/master/201-vm-sql-full-autobackup)

### Issue Details
The post install step of 201-vm-sql-full-autobackup fails when executing the PowerShell script. The failure is on the xSQLLogin AddSQLAUTH section. The error message says LoginType is invalid.

xSqlLogin AddSQLAUTH
{
...
LoginType = "SqlLogin"
...
}

Start in the 201-vm-sql-full-autobackup template linked in the issue and locate its post-install PowerShell script, then inspect the xSqlLogin AddSQLAUTH section. Check the xSQLLogin LoginType documentation or reproduce the deployment to confirm the accepted value. Done means the post-install step completes without the LoginType error.

Written by the indexing model from the issue text.