Migrate to python 3.10 (and fix code cov issue)

[JonathanCasey]

Why not?

Can start or-ing dicts together, which is nice.

...but it might fix the code coverage issue encountered on #32. By executing pytest -k 'test__filter_tasks_by_datetime' --cov-report=term-missing --cov=asana_extensions/asana and looking at the line numbers in the Missing column for the utils.py module, it can be seen that there is a miss in the _filter_tasks_by_datetime(). This seems to be related to this in pytest-cov, which references this issue in coveragepy and hints that this is a problem with an underlying mechanism in python itself, which coveragepy asserts on that issue (which was opened in 2012!) that it just got fixed THIS YEAR!

Will give it a try. If it fails, will find a work around to restore 100% test coverage. It seems likely putting anything meaningless in the else before the continue should work, as it seems like an optimization issue that is mismatched with how coverage is determined. A print() statement did the trick in a simple test.