Manually remove file to try to stop flaky tests on PyPy

Author: abravalheri

setuptools/tests/config/test_setupcfg.py

@@ -458,6 +458,8 @@ def test_invalid_options_previously_deprecated(
         with pytest.warns(SetuptoolsDeprecationWarning, match=re.escape(error_msg)):
             dist = get_dist(tmpdir).__enter__()
 
+        tmpdir.join('setup.cfg').remove()
+
         for field, value in invalid.items():
             attr = field.replace("-", "_").lower()
             assert getattr(dist.metadata, attr) == value