Allow empty custom registry
Allow empty custom registry

warmchang/minikube,kubernetes/minikube,warmchang/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube