adding namespace is not necessary.

[fuminori-ido-m]

Adding echo " namespace: monitoring" in build.sh looks no more necessary. It just duplicates the same line so that remove it.

I'm not sure which version of kubectl fixes, but at least the following works with my patch:

$ kubectl version
Client Version: version.Info{Major:"1", Minor:"15", GitVersion:"v1.15.3", GitCommit:"2d3c76f9091b6bec110a5e63777c332469e0cba2", GitTreeState:"clean", BuildDate:"2019-08-19T11:13:54Z", GoVersion:"go1.12.9", Compiler:"gc", Platform:"linux/amd64"}