fix: Allocate new slice for each batch in streaming reader

[congqixia]

Related to #33268

[sre-ci-robot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.10%. Comparing base (e895cfe) to head (d0577cc).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #33359      +/-   ##
==========================================
- Coverage   82.11%   82.10%   -0.02%     
==========================================
  Files        1012     1012              
  Lines      128829   128848      +19     
==========================================
+ Hits       105793   105794       +1     
- Misses      19062    19074      +12     
- Partials     3974     3980       +6     

Files	Coverage Δ
internal/storage/serde.go	87.95% <100.00%> (-0.03%)	⬇️

... and 31 files with indirect coverage changes

[tedxu]

/lgtm