fix: Make KeyLock obj pool size unlimited

[congqixia]

Related to #39181

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.12%. Comparing base (032292a) to head (1292873).
Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #39182      +/-   ##
==========================================
- Coverage   81.14%   81.12%   -0.03%     
==========================================
  Files        1395     1395              
  Lines      197434   197437       +3     
==========================================
- Hits       160217   160167      -50     
- Misses      31591    31627      +36     
- Partials     5626     5643      +17     

Components	Coverage Δ
Client	79.53% <ø> (ø)
Core	69.67% <ø> (+0.02%)	⬆️
Go	83.04% <ø> (-0.04%)	⬇️

Files with missing lines	Coverage Δ
pkg/util/lock/key_lock.go	81.00% <ø> (-9.00%)	⬇️

... and 26 files with indirect coverage changes

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