* Reduces test time from ~5 mins to ~30 seconds.
* Also converts to pytestCheckHook for better test control.
* Makes fetchFromGitHub variables match convention.
* remove pytest-randomly.
pytest-randomly will randomize test order &
reset random seeds between tests.
We don't want the random test ordering for reproducible builds, so we
remove it.
* Fixes flaky test "test_hashmap_old_version" by pinning pytest to v5,
corresponding to upstream issue:
https://github.com/adobe-type-tools/psautohint/issues/284#issuecomment-742800965
py3.psautohint: use pytest5
