Harden one test where it is tested.
All tests testing this:
testing/acceptance_test.py:184(TestGeneralUsage::test_not_collectable_arguments)
testing/acceptance_test.py:373(TestGeneralUsage::test_direct_addressing_notfound)
testing/acceptance_test.py:403(TestGeneralUsage::test_issue134_report_error_when_collecting_member[test_fun.py::test_a])
testing/acceptance_test.py:420(TestGeneralUsage::test_report_all_failed_collections_initargs)
testing/test_config.py:1309(test_config_blocked_default_plugins[python])
(via https://github.com/blueyed/pytest/pull/88)