Our macOS builds suddenly started failing. The packaging works, but trying to run the app gives an error:

[2445] Failed to execute script pyi_rth_pkgres
Traceback (most recent call last):
File "site-packages/PyInstaller/loader/rthooks/pyi_rth_pkgres.py", line 13, in <module>
File "/Users/runner/hostedtoolcache/Python/3.7.5/x64/lib/python3.7/site-packages/PyInstaller/loader/pyimod03_importers.py", line 623, in exec_module
exec(bytecode, module._dict_)
File "site-packages/pkg_resources/_init_.py", line 86, in <module>
ModuleNotFoundError: No module named 'pkg_resources.py2_warn'

I first thought this was related to recent upgrade to PyInstaller 3.6, but the 3.6 builds initially worked and downgrading to 3.5 does not help.

This is the last working build:

https://github.com/metabrainz/picard/commit/1636fcb31042e92507a42d27cdcdbd27efe1a3ca/checks?check_suite_id=395546866

This is the first time it failed:

https://github.com/metabrainz/picard/commit/d911df42a612657ed96e36a0825d8c767bac3aa5/checks?check_suite_id=396544013

The changes in this commit are not relevant for the failure, also the master of 1636fcb would fail the same. I can also reproduce the failing builds locally.