Make artifact_factory.py more memory efficient

[NicoHinderling]

changes:

1. Only read 4 bytes into memory rather than the whole file
2. Open ZIP file directly from path instead of loading into memory

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.75%. Comparing base (b66c16e) to head (805b188).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #311      +/-   ##
==========================================
- Coverage   77.75%   77.75%   -0.01%     
==========================================
  Files         142      142              
  Lines       11149    11148       -1     
  Branches     1185     1185              
==========================================
- Hits         8669     8668       -1     
  Misses       2059     2059              
  Partials      421      421              

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