fix: the retrieve plan on heap is used after free when reduce

[chyezh]

issue: #38731

[congqixia]

/lgtm

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chyezh, congqixia

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• internal/querynodev2/segments/OWNERS [congqixia]

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[mergify]

@chyezh E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[mergify]

@chyezh go-sdk check failed, comment rerun go-sdk can trigger the job again.

[codecov]

Codecov Report

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

Project coverage is 81.09%. Comparing base (dd81a13) to head (603d33f).
Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
internal/querynodev2/segments/result.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #38840      +/-   ##
==========================================
- Coverage   81.12%   81.09%   -0.03%     
==========================================
  Files        1385     1385              
  Lines      195922   195922              
==========================================
- Hits       158939   158883      -56     
- Misses      31396    31435      +39     
- Partials     5587     5604      +17     

Components	Coverage Δ
Client	79.12% <ø> (ø)
Core	69.45% <ø> (ø)
Go	83.05% <0.00%> (-0.04%)	⬇️

Files with missing lines	Coverage Δ
internal/querynodev2/segments/result.go	71.52% <0.00%> (ø)

... and 24 files with indirect coverage changes

[chyezh]

rerun go-sdk

[chyezh]

/run-cpu-e2e

[chyezh]

rerun ut