It seems that upstream has fixed line numbers in some of the expections
in Python 3.10.0rc1, so update the tests accordingly. This means that
test_non_async_in_async() gets the correct line again,
and test_default_except_error_postition() no longer suffers from
the apparent off-by-one problem.
This doesn't fix tests entirely with Python 3.10 but it's a step
forward.