feat: validate fieldOverrider operation

[chaunceyjiang]

What type of PR is this?
/kind feature

What this PR does / why we need it:

feat: validate fieldOverrider operation

Which issue(s) this PR fixes:
Part of #5608

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

`karmada-webhook`: validate fieldOverrider operation.

[codecov-commenter]

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Codecov Report

Attention: Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.

Project coverage is 36.54%. Comparing base (6e41d9b) to head (f45aedb).

Files with missing lines	Patch %	Lines
pkg/util/validation/validation.go	0.00%	12 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5671      +/-   ##
==========================================
- Coverage   36.56%   36.54%   -0.03%     
==========================================
  Files         648      648              
  Lines       45079    45091      +12     
==========================================
- Hits        16485    16480       -5     
- Misses      27351    27367      +16     
- Partials     1243     1244       +1     

Flag	Coverage Δ
unittests	36.54% <0.00%> (-0.03%)	⬇️

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[RainbowMango]

/retest

[chaunceyjiang]

/cc @RainbowMango @sophiefeifeifeiya PTAL.

[RainbowMango]

/assign

[RainbowMango]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: RainbowMango

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