MacOS segfault in get_default_conf_dirs

[totaam]

Could well be related to #3770.

When running from the bundled application, it segfaults.
When running from a jhbuild shell:

$ python3 -c "from xpra.platform.paths import get_default_conf_dirs;print(get_default_conf_dirs())"

** (process:53532): WARNING **: 21:53:03.180: Failed to load shared library 'libpango-1.0.0.dylib' referenced by the typelib: dlopen(libpango-1.0.0.dylib, 9): image not found
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/paths.py", line 83, in get_default_conf_dirs
    return envaslist_or_delegate("XPRA_DEFAULT_CONF_DIRS", do_get_default_conf_dirs)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/paths.py", line 29, in envaslist_or_delegate
    return impl(*args)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/darwin/paths.py", line 75, in do_get_default_conf_dirs
    return [os.path.join(get_resources_dir(), "etc", "xpra")]
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/paths.py", line 199, in get_resources_dir
    return env_or_delegate("XPRA_RESOURCES_DIR", do_get_resources_dir)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/paths.py", line 34, in env_or_delegate
    return impl(*args)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/darwin/paths.py", line 27, in do_get_resources_dir
    macapp = get_OSXApplication()
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/xpra/platform/darwin/__init__.py", line 39, in get_OSXApplication
    from gi.repository import GtkosxApplication #@UnresolvedImport
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 672, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 632, in _load_backward_compatible
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/importer.py", line 144, in load_module
    importlib.import_module('gi.repository.' + dep.split("-")[0])
  File "/Users/macos/gtk/inst/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 672, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 632, in _load_backward_compatible
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/importer.py", line 144, in load_module
    importlib.import_module('gi.repository.' + dep.split("-")[0])
  File "/Users/macos/gtk/inst/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 672, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 632, in _load_backward_compatible
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/importer.py", line 144, in load_module
    importlib.import_module('gi.repository.' + dep.split("-")[0])
  File "/Users/macos/gtk/inst/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 672, in _load_unlocked
  File "<frozen importlib._bootstrap>", line 632, in _load_backward_compatible
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/importer.py", line 145, in load_module
    dynamic_module = load_overrides(introspection_module)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/overrides/__init__.py", line 118, in load_overrides
    override_mod = importlib.import_module(override_package_name)
  File "/Users/macos/gtk/inst/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/overrides/Pango.py", line 41, in <module>
    FontDescription = override(FontDescription)
  File "/Users/macos/gtk/inst/lib/python3.10/site-packages/gi/overrides/__init__.py", line 195, in override
    assert g_type != TYPE_NONE
AssertionError

assert g_type != TYPE_NONE, we meet again: Xpra-org/gtk-osx-build#21

[totaam]

Probably caused by jralls/gtk-osx-build@9008438 which contains:
Unfortunately there's no way to get the config object from the project to find out if we're building python3. We test the modules list here but that's not really reliable because python3 might be pulled in as a dependency by another module

https://github.com/jralls/gtk-osx-build/blob/db1c8631d2c2ac2f8097a4de6bf7c47add6dfb35/jhbuildrc-gtk-osx#L623-L626

So this should make it all better: Xpra-org/gtk-osx-build@2cc47e1

[totaam]

Was probably cause by pyobjc, fixed by downgrading back to v8.2: a0a7e22

[totaam]

The more likely explanation is this mess: Xpra-org/gtk-osx-build#22 (comment)