Use preview terratest Azure module to manage BYO_RG instead of golang cmds

[NathanielRose]

As a:
Devloper, Infrastructure Operator

I want:
Use upcoming terratest support for Azure

So that:
Bedrock uses the Terratest framework for deploying successful BYO_RGs instead of native golang cmds.

Describe the solution you'd like:

testrg:= azure createTargetAzureResourceGroupName(resourceGroupName string) (string, error)
.
.
.
"global_resource_group_name":     testrg,