fix: Fix stats task wrong RootPath when upload binlog

[xiaocai2333]

issue: #38336

[czs007]

/approve
/lgtm

[sre-ci-robot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.98%. Comparing base (b9d8c5c) to head (05fc163).
Report is 11 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #38539       +/-   ##
===========================================
+ Coverage   69.34%   80.98%   +11.63%     
===========================================
  Files         292     1378     +1086     
  Lines       26168   194187   +168019     
===========================================
+ Hits        18146   157255   +139109     
- Misses       8022    31384    +23362     
- Partials        0     5548     +5548     

Components	Coverage Δ
Client	74.52% <ø> (∅)
Core	69.34% <ø> (-0.01%)	⬇️
Go	83.03% <100.00%> (∅)

Files with missing lines	Coverage Δ
internal/indexnode/task_stats.go	70.33% <100.00%> (ø)

... and 1091 files with indirect coverage changes

[xiaocai2333]

rerun ut