[fix][backend] gopool errors handler

[lsy357]

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fix

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[codecov]

Codecov Report

❌ Patch coverage is 90.47619% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
backend/pkg/lang/goroutine/pool.go	90.00%	1 Missing and 1 partial ⚠️

@@           Coverage Diff           @@
##             main     #561   +/-   ##
=======================================
  Coverage   77.82%   77.82%           
=======================================
  Files         670      670           
  Lines       76115    76130   +15     
=======================================
+ Hits        59238    59251   +13     
- Misses      13416    13417    +1     
- Partials     3461     3462    +1     

Flag	Coverage Δ
unittests	77.82% <90.47%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...aluation/domain/service/expt_run_item_turn_impl.go	86.46% <100.00%> (ø)
backend/pkg/lang/goroutine/pool.go	89.47% <90.00%> (+2.51%)	⬆️

... and 2 files with indirect coverage changes

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