Support immediate deletion of no longer referenced bundle resources

[Burr]

Right now when a resource is no longer referenced in a bundle, it will not be deleted by Smith until the bundle is in a Ready state. However, in some cases, it might be preferred to delete the resource immediately when it is detected that it is no longer needed.

One example is a HorizontalPodAutoscaler (which will depend on a Deployment) - if removed from the bundle, it should be deleted before the bundle becomes ready, otherwise it will continue to update the Deployment object it references.