Simplify client calls for machine resources

[anishasthana]

We are currently using a large number of api-specific objects to make client calls like get/put / whatever. We should be able to do all of these using the default kubernetes client. https://github.com/opendatahub-io/modelmesh-serving/blob/main/controllers/servingruntime_controller.go#L134-L151 has an example for secrets, but similar logic should function for machinesets and the like.

https://github.com/project-codeflare/instascale/blob/main/controllers/appwrapper_controller.go#L118-L121