Implement provider config abstraction for GCP

Background

To enable the MachineProvider to be platform agnostic, we have an abstraction on the provider configs that provides functionality like extracting or injecting a failure domain from the config and spitting out the config as a structured object.

This needs to be implemented so that we can continue work on the core of the MachineProvider.

The GCP implementation should be based on the AWS implementation which should already be implemented.

The code can be found https://github.com/openshift/cluster-control-plane-machine-set-operator/tree/main/pkg/machineproviders/providers/openshift/machine/v1beta1/providerconfig

Steps

• Review the AWS implementation and general package interface
• Understand the desired behaviour
• Extend the functionality to implement GCP support based on the AWS support
• Ensure appropriate tests are added to mirror those in the AWS implementation

Stakeholders

• Cluster Infra (Joel)

Definition of Done

• GCP implementation of the provider config abstraction is fully implemented

• Docs

• N/A

• Testing

• N/A