Windows: Use vnet resource group as build_resource_group_name instead of creating temporary resource group

[AbelHu]

Is your feature request related to a problem?/Why is this needed

no

Describe the solution you'd like in detail

https://www.packer.io/plugins/builders/azure/arm#build_resource_group_name I tried to use the pre-created rg VNET_RESOURCE_GROUP_NAME as build_resource_group_name for packer but it did not work. Need to investigate it. If it works, all resources created by packer can be in the same pre-created resource group and it will save the time to delete it with --no-wait. Currently we need to wait the Windows build VM to be deleted before deleting the pre-created rg VNET_RESOURCE_GROUP_NAME

Describe alternatives you've considered

Additional context