Test suite fails if unidecode is installed

[mgorny]

$ python --version
Python 3.11.3
$ pip list
Package             Version
------------------- -------
asgiref             3.6.0
coverage            7.2.5
Django              4.2.1
django-taggit       4.0.0
djangorestframework 3.14.0
pip                 23.0.1
pytz                2023.3
setuptools          67.6.1
sqlparse            0.4.4
Unidecode           1.3.6
wheel               0.40.0
$ python -m django test --settings=tests.settings
Found 378 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
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======================================================================
FAIL: test_old_slugs (tests.test_models.TestSlugification.test_old_slugs)
Test that the setting that gives us the old slugification behavior
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/tmp/django-taggit-4.0.0/tests/test_models.py", line 27, in test_old_slugs
    self.assertEqual([tag.slug for tag in sample_obj.tags.all()], [""])
AssertionError: Lists differ: ['ai-ueo'] != ['']

First differing element 0:
'ai-ueo'
''

- ['ai-ueo']
+ ['']

----------------------------------------------------------------------
Ran 378 tests in 8.998s

FAILED (failures=1, skipped=7)
Destroying test database for alias 'default'...