Azure: Allow user to specify resource group for NodePool resources

User Story:

As ARO/HCP provider, I want to be able to:

• specify which resource group is going to be used for the resources in the customer side

so that I can achieve

• control over where resources get allocated instead of getting defaults.

Acceptance Criteria:

Description of criteria:

• Customer side resources get created in the API specified resource group.

Engineering Details:

 This requires a design proposal so OCM knows where to specify the resource group
 This requires might require a feature gate in case we don't want it for self-managed.