Cest _failed hook not called on \Throwable

Tests that error from the new tree of php7 errors don't get their _failed method called. Happy to write a patch myself but wanted to make sure this is an issue first or if there's something different I should be doing

https://github.com/Codeception/Codeception/blob/bd6ad8af1fa7cd12684f0287374b9fe71a8c958a/src/Codeception/Test/Cest.php#L86