$ git --versiongit version 2.30.0

======================================================================ERROR: test_index_file_diffing (test.test_index.TestIndex)----------------------------------------------------------------------Traceback (most recent call last):  File "/tmp/GitPython/test/lib/helper.py", line 140, in repo_creator    return func(self, rw_repo)  File "/tmp/GitPython/test/test_index.py", line 378, in test_index_file_diffing    self.assertRaises(CheckoutError, index.checkout, "doesnt_exist_ever.txt.that")  File "/usr/lib/python3.9/unittest/case.py", line 733, in assertRaises    return context.handle('assertRaises', args, kwargs)  File "/usr/lib/python3.9/unittest/case.py", line 201, in handle    callable_obj(*args, **kwargs)  File "/tmp/GitPython/git/index/util.py", line 76, in check_default_index    return func(self, *args, **kwargs)  File "/tmp/GitPython/git/index/base.py", line 1133, in checkout    self._flush_stdin_and_wait(proc, ignore_stdout=True)  File "/tmp/GitPython/git/index/base.py", line 980, in _flush_stdin_and_wait    proc.wait()  File "/tmp/GitPython/git/cmd.py", line 408, in wait    raise GitCommandError(self.args, status, errstr)git.exc.GitCommandError: Cmd('/usr/bin/git') failed due to: exit code(1)  cmdline: /usr/bin/git checkout-index --index --stdin  stderr: 'git checkout-index: doesnt_exist_ever.txt.that is not in the cache'