[Bug]: avro_dict_to_beam_row negative integer incorrectly converts to uint

[DKER2]

fixes #34438

Revert #30770 as we already has permanent fix #34354. #30770 is a workaround to avoid negative value in https://github.com/apache/beam/blob/master/sdks/java/core/src/main/java/org/apache/beam/sdk/util/VarInt.java#L103-L109

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 57.82%. Comparing base (160dffd) to head (c59ba99).
Report is 1338 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #34542      +/-   ##
============================================
+ Coverage     57.32%   57.82%   +0.49%     
  Complexity     1474     1474              
============================================
  Files           967     1004      +37     
  Lines        153754   157785    +4031     
  Branches       1076     1076              
============================================
+ Hits          88140    91233    +3093     
- Misses        63410    64348     +938     
  Partials       2204     2204              

Flag	Coverage Δ
python	81.15% <100.00%> (-0.26%)	⬇️

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[Abacn]

Thank you!