Fix staging java source/python source

[damccorm]

Both these workflows were failing. The java source was accidentally modified as part of the pyproject.toml work, this reverts it back to its previous state. The python source never worked and had a bunch of issues that needed fixing.

Example successful workflow - https://github.com/apache/beam/actions/runs/6754402902/job/18361839573

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[codecov]

Codecov Report

Merging #29299 (50c1522) into master (f25c441) will decrease coverage by 0.01%.
Report is 10 commits behind head on master.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #29299      +/-   ##
==========================================
- Coverage   38.30%   38.30%   -0.01%     
==========================================
  Files         690      690              
  Lines      102045   102048       +3     
==========================================
  Hits        39085    39085              
- Misses      61377    61380       +3     
  Partials     1583     1583              

Flag	Coverage Δ
python	29.88% <ø> (-0.01%)	⬇️

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see 2 files with indirect coverage changes

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[Abacn]

thanks