Update addons.md
Update addons.md

fix typos - should be an upper case like in other commands.
warmchang/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube