bdist_mac: skip text files in set_relative_reference_paths

[micahflee]

I'm trying to make a release of OnionShare on an ARM64 Apple Silicon Mac. When run bdist_mac, it fails with this error:

Setting relative_reference_path for: Mach-O File: /Users/user/Library/Caches/pypoetry/virtualenvs/onionshare-aqknF-N0-py3.11/lib/python3.11/site-packages/cx_Freeze/initscripts/frozen_application_license.txt
Resolved rpath:
Loaded libraries:
Applying AdHocSignature
/Users/user/code/onionshare/desktop/build/OnionShare.app/Contents/MacOS/frozen_application_license.txt: No such file or directory
error: [Errno 2] No such file or directory: '/Users/user/code/onionshare/desktop/build/OnionShare.app/Contents/MacOS/frozen_application_license.txt'

Looking at the code I saw that the set_absolute_reference_paths function has similar code that skips txt and zip files, and so this makes set_relative_reference_paths skip text files too, as these can't be code signed. This patch fixes the issue I ran into.

[codecov]

Codecov Report

All modified lines are covered by tests ✅

Comparison is base (8b6d744) 51.63% compared to head (ad8eb8e) 39.79%.

❗ Current head ad8eb8e differs from pull request most recent head 5f4a402. Consider uploading reports for the commit 5f4a402 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2102       +/-   ##
===========================================
- Coverage   51.63%   39.79%   -11.85%     
===========================================
  Files          72       72               
  Lines        5924     5926        +2     
===========================================
- Hits         3059     2358      -701     
- Misses       2865     3568      +703     

Files	Coverage Δ
cx_Freeze/command/bdist_mac.py	51.02% <100.00%> (+0.40%)	⬆️

... and 16 files with indirect coverage changes

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[marcelotduarte]

What version of cx_Freeze did you use? I'm asking because in the latest version, only executables are copied to "Contents/MacOS", all other files are copied to the "Resources" directory:
https://github.com/marcelotduarte/cx_Freeze/blob/main/cx_Freeze/command/bdist_mac.py#L460-L468