BuildHandlerChain builds a handler chain with a base handler and CompletedConfig.

NewBaseHandler takes in CompletedConfig and returns a handler.

WaitForAPIServer waits for the API Server's /healthz endpoint to report "ok" with timeout.

CompletedConfig same as Config, just to swap private object.

Config is the main context object for the controller manager.

InsecureServingInfo is the main context object for the insecure http server.