🌱 Add function to controllerutil RemoveControllerReference to remove controller references from objects

[troy0820]

When using the function SetControllerReference it will error when trying to overwrite the controller reference. In issue #2381 the method used to circumvent the errors is to remove the controller reference and then reapply the new controller reference. There is no exposed method to do this. This mimics the behavior of removing a finalizer

• Add function with description
• Add test with coverage

Resolves #2381

Release note:

Add function RemoveControllerReference to pkg/controller/controllerutil 
to allow the removal of the owner reference of the controlled object.

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: troy0820
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[vincepri]

/ok-to-test

[troy0820]

/assign @vincepri

Could you take another look at this @vincepri, not sure what else we need with this.

[troy0820]

Closing and deferring all feedback to #2462

Same method but allows us to utilize this function to remove owner references and/or controller references.