Remove register Microsoft.Subscription from azure
Remove register Microsoft.Subscription from azure

This commit rolls back a change that was added in as part of https://github.com/rancher/machine/commit/b13f35b91cacbc867e7a0fb584ae65dffc3bb1aa#diff-93a074128ed8940ea0dafbd000270978R349.

`RegisterResourceProviders` makes a call to Azure to ensure that the current Azure subscription has the ability to deploy a resource for a given [resource provider](https://docs.microsoft.com/en-us/azure/azure-resource-manager/management/resource-providers-and-types). Rancher does not require the ability to deploy a new subscription, so registering the Microsoft.Subscriptions resource provider is unnecessary. However, creating a resource group (Microsoft.Resources), a storage account (Microsoft.Storage), a network security group (Microsoft.Network), and a Virtual Machine (Microsoft.Compute) should still be required.

ibuildthecloud/machine,ibuildthecloud/machine