ci: test_runner uses a UNIX-only Python function (os.killpg)

[darosior]

Encountered by the Win64 CI in #23074

Traceback (most recent call last):
  File "C:\Users\ContainerAdministrator\AppData\Local\Temp\cirrus-ci-build\test\functional\test_runner.py", line 797, in <module>
    main()
  File "C:\Users\ContainerAdministrator\AppData\Local\Temp\cirrus-ci-build\test\functional\test_runner.py", line 446, in main
    run_tests(
  File "C:\Users\ContainerAdministrator\AppData\Local\Temp\cirrus-ci-build\test\functional\test_runner.py", line 567, in run_tests
    os.killpg(os.getpgid(0), signal.SIGKILL)
AttributeError: module 'os' has no attribute 'killpg'

[hebasto]

See:

• test: don't try and use os.killpg() on Windows #22936
• qa: Ignore --failfast option of test_runner.py on Windows #22980

[maflcko]

Thanks for the report, however I am going to close this bug, as it has been removed from ci in #23513.

The bug still does exist on Windows, but I don't think we have any users on Windows that run the tests with --failfast. If I am wrong, please let me know and this bug can be reopened or a new one be opened.