fix: [2.5] empty row for sparse vector

[xiaofan-luan]

fix: #40584
pr: #40585

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[codecov]

Codecov Report

Attention: Patch coverage is 94.11765% with 1 line in your changes missing coverage. Please review.

Project coverage is 80.95%. Comparing base (bd41701) to head (a6a87ae).
Report is 2 commits behind head on 2.5.

Files with missing lines	Patch %	Lines
internal/util/importutilv2/parquet/field_reader.go	94.11%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##              2.5   #40586   +/-   ##
=======================================
  Coverage   80.94%   80.95%           
=======================================
  Files        1421     1421           
  Lines      200868   200879   +11     
=======================================
+ Hits       162597   162626   +29     
+ Misses      32596    32586   -10     
+ Partials     5675     5667    -8     

Components	Coverage Δ
Client	79.77% <ø> (ø)
Core	70.36% <ø> (ø)
Go	82.84% <94.11%> (+0.01%)	⬆️

Files with missing lines	Coverage Δ
internal/util/importutilv2/parquet/field_reader.go	64.43% <94.11%> (-0.18%)	⬇️

... and 38 files with indirect coverage changes

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[czs007]

/approve
/lgtm

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: czs007, xiaofan-luan

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