Implement owner reference additions for existing Machines owned by CPMS

Background

When a ControlPlaneMachineSet is added to an existing cluster, we expect it to own (via an owner reference) the Machines that it targets. We should ensure that, once we have gather the MachineInfo from the MachineProvider, each Machine has an owner reference, and, if it is missing, should attempt to patch the owner references using partial object metadata. (Note, if we use this approach, the code should be agnostic of the underlying Machine type)

This should be implemented here  and should satisfy these  tests.

Whoever ends up implementing this may want to talk to Joel about the PartialObjectMetadata and how this should be implemented (or they may want to work it out for themselves, up to them)

Steps

• Review the tests cases and function description to understand what the expected behaviour is
• Implement the behaviour of the function based on prescribed behaviour in the tests
• Ensure linting passes (make lint) and think about the code layout, it is clean?
• Consider any additional tests that may need to be added

Stakeholders

• Cluster Infra (Joel)

Definition of Done

• When a CPMS is added, Machines have owner references attached

• Docs

• N/A

• Testing

• Existing unit tests and any additional tests that may be required