feat: optimize piece download failed handler

[gaius-qi]

Description

Related Issue

Motivation and Context

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.

[codecov]

Codecov Report

Merging #2883 (e6d2492) into main (86ce09f) will decrease coverage by 0.02%.
Report is 1 commits behind head on main.
The diff coverage is 76.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2883      +/-   ##
==========================================
- Coverage   50.97%   50.95%   -0.02%     
==========================================
  Files         161      161              
  Lines       21746    21760      +14     
==========================================
+ Hits        11084    11088       +4     
- Misses      10001    10009       +8     
- Partials      661      663       +2     

Flag	Coverage Δ
unittests	50.95% <76.00%> (-0.02%)	⬇️

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

Files	Coverage Δ
scheduler/scheduling/scheduling.go	81.91% <100.00%> (+0.07%)	⬆️
scheduler/service/service_v2.go	85.16% <71.42%> (-0.40%)	⬇️

... and 2 files with indirect coverage changes