test_tarfile fails on file modes

[furkanonder]

Checklist

• I am confident this is a bug in CPython, not a bug in a third-party project
• I have searched the CPython issue tracker, and am confident this bug has not been reported before

[ted@rasp4 cpython]$ ./python -m test test_tarfile
0:00:00 load avg: 0.27 Run tests sequentially
0:00:00 load avg: 0.27 [1/1] test_tarfile
test test_tarfile failed -- Traceback (most recent call last):
  File "/home/ted/cpython/Lib/test/test_tarfile.py", line 3679, in test_modes
    self.expect_file('all_bits', mode='?rwsrwsrwt')
  File "/home/ted/cpython/Lib/test/test_tarfile.py", line 3429, in expect_file
    self.assertEqual(got, mode)
AssertionError: '?rwsrwxrwt' != '?rwsrwsrwt'
- ?rwsrwxrwt
?       ^
+ ?rwsrwsrwt
?       ^

Your environment

• CPython versions tested on: Python 3.13.0a0
• Operating system and architecture: Manjaro ARM Linux aarch64 | Raspberry Pi 4 Model B Rev 1.5
• Configuration of CPython: ./configure --with-pydebug

Linked PRs

• gh-107902: Don't test setting suid/sgid on systems that don't support them #108368
• [3.10] gh-107902: gh-108948: Don't test setting suid/sgid/sticky on systems that don't support them (GH-108368) (GH-109697) #125255
• [3.9] gh-107902: gh-108948: Don't test setting suid/sgid/sticky on systems that don't support them (GH-108368) (GH-109697) #125576
• [3.9] [3.10] gh-107902: gh-108948: Don't test setting suid/sgid/sticky on systems that don't support them (GH-108368) (GH-109697) (GH-125255) #125835

[encukou]

Thanks for the report!
The test fix was merged in main. Let me know if you need a backport -- I won't make one by default since this is only a test issue for a platform without buildbots. I assume you can patch/skip the test on your build.