add ut for cmdinit

[AllenZMC]

What type of PR is this? /kind cleanup

What this PR does / why we need it: add ut for cmdinit Which issue(s) this PR fixes: Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[karmada-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[AllenZMC]

@XiShanYongYe-Chang @RainbowMango