fix: Retain collection early to prevent it from being released before query completion

[xiaocai2333]

issue: #45314

This PR only ensures that no panic occurs. However, we still need to provide protection for the delegator handling ongoing query tasks.

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 41.64%. Comparing base (e8bdc3f) to head (88278c0).

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #45413       +/-   ##
===========================================
- Coverage   83.58%   41.64%   -41.95%     
===========================================
  Files         518     1209      +691     
  Lines       80838   190688   +109850     
===========================================
+ Hits        67570    79415    +11845     
- Misses      13268   110942    +97674     
- Partials        0      331      +331     

Components	Coverage Δ
Client	∅ <ø> (∅)
Core	83.58% <ø> (ø)
Go	9.57% <ø> (∅)
see 691 files with indirect coverage changes

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[mergify]

@xiaocai2333 cpu-e2e job failed, comment /run-cpu-e2e can trigger the job again.

[mergify]

@xiaocai2333 go-sdk check failed, comment rerun go-sdk can trigger the job again.