Fix overflow when read 4GB+ fiiles on 32-bit targets

[Mingun]

Added new check to CI and check that tests (for sync and async methods) are failed before the fix (I checked) and passed after.

Fixes #751

Commit which is failed before the fix: Mingun@f5608f0
Job result for it: https://github.com/Mingun/quick-xml/actions/runs/9650155180/job/26615200796

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 73.33333% with 20 lines in your changes missing coverage. Please review.

Project coverage is 60.28%. Comparing base (7558577) to head (ef954dc).
Report is 47 commits behind head on master.

Files	Patch %	Lines
src/utils.rs	44.44%	20 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master     #769      +/-   ##
==========================================
- Coverage   61.81%   60.28%   -1.54%     
==========================================
  Files          41       41              
  Lines       16798    16226     -572     
==========================================
- Hits        10384     9782     -602     
- Misses       6414     6444      +30     

Flag	Coverage Δ
unittests	60.28% <73.33%> (-1.54%)	⬇️

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