fix: Skip erase field if index build on PK field

[congqixia]

Related to #39339

[mergify]

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[mergify]

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[codecov]

Codecov Report

Attention: Patch coverage is 75.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 81.00%. Comparing base (0461ddf) to head (16b62e5).
Report is 11 commits behind head on master.

Files with missing lines	Patch %	Lines
...rnal/core/src/segcore/ChunkedSegmentSealedImpl.cpp	50.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #39370       +/-   ##
===========================================
+ Coverage   69.47%   81.00%   +11.53%     
===========================================
  Files         300     1407     +1107     
  Lines       26903   198527   +171624     
===========================================
+ Hits        18692   160826   +142134     
- Misses       8211    32041    +23830     
- Partials        0     5660     +5660     

Components	Coverage Δ
Client	79.50% <ø> (∅)
Core	69.48% <75.00%> (+<0.01%)	⬆️
Go	82.94% <ø> (∅)

Files with missing lines	Coverage Δ
internal/core/src/segcore/SegmentSealedImpl.cpp	84.08% <100.00%> (+0.01%)	⬆️
...rnal/core/src/segcore/ChunkedSegmentSealedImpl.cpp	22.93% <50.00%> (+0.07%)	⬆️

... and 1107 files with indirect coverage changes

[czs007]

/approve
/lgtm

[sre-ci-robot]

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