Need to add namespace to katib, cluster level scope is not necessary

[bryandai]

/kind bug

What steps did you take and what happened:
try to launch katib to a ns limit k8s, seems ns should be set for controller and clusterRole change to Role also works

What did you expect to happen:
add ns, remove cluster level scope

[hougangliu]

@wuyinzhenjun can you detail more about what this issue is about? Have no idea about what add namespace to katib means
Thanks

[gaocegege]

Dup with #162

/close

[k8s-ci-robot]

@gaocegege: Closing this issue.

In response to this:

Dup with #162

/close

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