`test_pyrepl.test_dumb_terminal_exits_cleanly` fails under Fish when run in VS Code's terminal

[brettcannon]

Bug report

Bug description:

This is under VS Code insiders on Windows with a checkout in WSL.

➲ ./python -m test test_pyrepl
Using random seed: 2979483264
0:00:00 load avg: 0.09 Run 1 test sequentially in a single process
0:00:00 load avg: 0.09 [1/1] test_pyrepl
test test_pyrepl failed -- Traceback (most recent call last):
  File "/home/brett/Repositories/python/cpython/Lib/test/test_pyrepl/test_pyrepl.py", line 1376, in test_dumb_terminal_exits_cleanly
    self.assertNotIn("Traceback", output)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^
AssertionError: 'Traceback' unexpectedly found in 'exit()\r\nPython 3.15.0a0 (heads/main-dirty:d7dbde89588, Aug  8 2025, 14:49:47) [Clang 14.0.6 ] on linux\r\nType "help", "copyright", "credits" or "license" for more information.\r\nTraceback (most recent call last):\r\n  File "/home/brett/.vscode-server-insiders/data/User/workspaceStorage/0abd4bd2132dfcbfde5adbe8d7792ee2/ms-python.python/pythonrc.py", line 5, in <module>\r\n    import readline\r\nModuleNotFoundError: No module named \'readline\'\r\nwarning: can\'t use pyrepl: terminal doesn\'t have the required clear capability; TERM=dumb\r\n>>> '

0:00:04 load avg: 0.17 [1/1/1] test_pyrepl failed (1 failure)

== Tests result: FAILURE ==

1 test failed:
    test_pyrepl

Total duration: 4.0 sec
Total tests: run=202 failures=1 skipped=17
Total test files: run=1/1 failed=1
Result: FAILURE

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux