port to ufonormalizer-0.6.1 (from 0.6.0)

[trofi]

In NixOS/nixpkgs#141423 NixOS noticed that after update of ufonormalizer from 0.6.0 to 0.6.1 some tests started failing as

=================================== FAILURES ===================================
___________________ test_ufo3_masters[args0-ufo3regular.ufo] ___________________

args = ['_0'], ufo_filename = 'ufo3regular.ufo'

    @pytest.mark.parametrize('args, ufo_filename', [
        (['_0'], 'ufo3regular.ufo'),  # hint/remove overlap/normalize/round
        (['_1'], 'ufo3regular.ufo'),  # for testing instance removal
        (['_2', 'a', 'c', 'n'], 'ufo3medium.ufo'),  # round only
        (['_3', 'a', '=ufo-version', '_2'], 'ufo3semibold.ufo'),  # no hint UFO v2
    ])
    def test_ufo3_masters(args, ufo_filename):
        runner(['-t', TOOL, '-o', 'd',
                f'_{get_input_path("ufo3.designspace")}', 'i'] + args)
        expected_path = _get_output_path(ufo_filename, 'expected_output')
        actual_path = _get_output_path(ufo_filename, 'temp_output')
>       assert differ([expected_path, actual_path])
E       AssertionError: assert False
E        +  where False = differ(['/build/afdko-3.5.1/tests/makeinstancesufo_data/expected_output/ufo3regular.ufo', '/build/afdko-3.5.1/tests/makeinstancesufo_data/temp_output/ufo3regular.ufo'])

tests/makeinstancesufo_test.py:133: AssertionError
----------------------------- Captured stderr call -----------------------------
WARNING:afdko.makeinstancesufo:Instance at index 0 has no 'familyname' attribute.
WARNING:afdko.makeinstancesufo:Instance at index 0 has no 'postscriptfontname' attribute.
WARNING:afdko.makeinstancesufo:Instance at index 0 has no 'stylename' attribute.

The change looks minor, but I'm not sure why it breaks afdko: unified-font-object/ufoNormalizer@0.6.0...0.6.1

Would it make sense to port to most recent 0.6.1?

Thanks!

[trofi]

Bisected down to unified-font-object/ufoNormalizer@2d4c06c "Do not write empty keys"

[frankrolf]

I think this would be a case where the test data needs changing.

[frankrolf]

Background:
My fix to ufonormalizer no longer writes the layerinfo.plist lib key if it’s empty, and consequently also does not write an empty layerinfo.plist file.
The test failures could be fixed by just just removing layerinfo.plist from the glyphs/ and processedGlyphs/ directories (in the “expected output” UFOs)