test_chown() is broken

[ligurio]

Traceback (most recent call last):                                                                                                                
  File "/home/sergeyb/sources/unreliablefs/tests/test_unreliablefs.py", line 146, in test_chown                                                   
    os.chown(filename, uid_new, -1)                                                                                                               
PermissionError: [Errno 1] Operation not permitted: '/tmp/pytest-of-sergeyb/pytest-7/test_chown0/mnt/testfile_1'  

[ligurio]

perhaps the solution is -o allow_root