upstream-dev pint tests are failing

[dcherian]

https://github.com/xarray-contrib/cf-xarray/runs/6729119063?check_suite_focus=true

________________ ERROR collecting cf_xarray/tests/test_units.py ________________
cf_xarray/tests/test_units.py:11: in <module>
    from ..units import units as ureg
cf_xarray/units.py:81: in <module>
    pint.unit.UnitDefinition("percent", "%", (), pint.converters.ScaleConverter(0.01))
E   AttributeError: module 'pint' has no attribute 'unit'
________________ ERROR collecting cf_xarray/tests/test_units.py ________________
cf_xarray/tests/test_units.py:11: in <module>
    from ..units import units as ureg
cf_xarray/units.py:81: in <module>
    pint.unit.UnitDefinition("percent", "%", (), pint.converters.ScaleConverter(0.01))
E   AttributeError: module 'pint' has no attribute 'unit'
=================================== FAILURES ===================================
_________________________ test_coordinates_quantified __________________________
[gw1] linux -- Python 3.10.4 /usr/share/miniconda/envs/cf_xarray_test/bin/python
    @requires_pint
    def test_coordinates_quantified():
        # note: import order is important
>       from .. import units  # noqa
cf_xarray/tests/test_accessor.py:222: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
cf_xarray/units.py:17: in <module>
    def short_formatter(unit, registry, **options):
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
func = <function short_formatter at 0x7f990adb84c0>
    def wrapper(func):
        if name in _FORMATTERS:
>           raise ValueError(f"format {name:!r} already exists")  # or warn instead
E           ValueError: Invalid format specifier
/usr/share/miniconda/envs/cf_xarray_test/lib/python3.10/site-packages/pint/formatting.py:160: ValueError

[keewis]

both UnitDefinition and ScaleConverter are now in pint.facets.plain, but I'm not sure what is public API and what isn't.

As for the second failing test: I have no idea. What is the type of name?