Package subcommands of karmadactl to make it clearer

[lonelyCZ]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

Package subcommands of karmadactl to make it clearer, and it is easy to add UT for subcommands.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[RainbowMango]

Please assign it to me after you fixed the CI.

[lonelyCZ]

Please assign it to me after you fixed the CI.

Ok, I will fix it after #2589 #2610 merged.

[XiShanYongYe-Chang]

This job will make the package of karmadactl clearer, thanks~

[XiShanYongYe-Chang]

Hi @lonelyCZ, How about continuing with this refactoring?

[lonelyCZ]

How about continuing with this refactoring?

All right, it can be pushed forward after #2694 merged.

[codecov-commenter]

Codecov Report

Merging #2664 (aa2a3c8) into master (393fb9d) will increase coverage by 5.61%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #2664      +/-   ##
==========================================
+ Coverage   33.37%   38.98%   +5.61%     
==========================================
  Files         200      187      -13     
  Lines       19750    16897    -2853     
==========================================
- Hits         6591     6588       -3     
+ Misses      12765     9914    -2851     
- Partials      394      395       +1     

Flag	Coverage Δ
unittests	38.98% <0.00%> (+5.61%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pkg/karmadactl/taint/taint.go	43.75% <0.00%> (ø)
pkg/util/worker.go	66.66% <0.00%> (-4.77%)	⬇️
pkg/karmadactl/cmdinit/utils/format.go	9.19% <0.00%> (ø)
pkg/karmadactl/apply/apply.go
pkg/karmadactl/cordon/cordon.go
pkg/karmadactl/deinit/deinit.go
pkg/karmadactl/describe/describe.go
pkg/karmadactl/exec/exec.go
pkg/karmadactl/get/get.go
pkg/karmadactl/join/join.go
... and 6 more

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[lonelyCZ]

/cc @RainbowMango @XiShanYongYe-Chang

[RainbowMango]

/assign
I'll look at it tomorrow.

[RainbowMango]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: RainbowMango

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