use_2to3 was removed from setuptools with version 58.0.0. There is an
upstream issue for this error
(https://github.com/indigo-dc/udocker/issues/358) and has been resolved
with commit
9f7d6c5f9a.
We apply this commit as a patch.
Disable test_02__load_structure because it fails with a
unittest.mock.InvalidSpecError.
The latest changes to support better cross-compilation compatibility
have introduced a stricter handling of dependency specifications in
python. Since b4acd97, mock and nosetest should be checkInputs, since
they are used for testing.
Fixes: #56972