python3Packages.sanic: disable failing test on darwin (#479175)

    # Our mailcap database has a different mime type name for xml documentations

    # AssertionError: assert 'text/xml; charset=utf-8' == 'application/xml'

    "test_guess_content_type"

  ]

  ++ lib.optionals stdenv.hostPlatform.isDarwin [

    # KeyError: "getgrnam(): name not found: 'root'"

    "test_validate_group_sets_gid"

  ];

  disabledTestPaths = [