chore: Use != for RV comparison

[whitewindmills]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
There is no need to use reflect.DeepEqual for string comparison, so to improve it!

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[XiShanYongYe-Chang]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: XiShanYongYe-Chang

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• pkg/controllers/OWNERS [XiShanYongYe-Chang]

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 53.12%. Comparing base (3ff8700) to head (9c70349).
Report is 4 commits behind head on master.

Files	Patch %	Lines
pkg/controllers/status/common.go	0.00%	1 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4911      +/-   ##
==========================================
- Coverage   53.12%   53.12%   -0.01%     
==========================================
  Files         251      251              
  Lines       20415    20415              
==========================================
- Hits        10846    10845       -1     
- Misses       8855     8856       +1     
  Partials      714      714              

Flag	Coverage Δ
unittests	53.12% <0.00%> (-0.01%)	⬇️

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