INFO: no py38

[loriab]

No, we can't use Python 3.8 for a bit until a tweak goes into pint, hgrecco/pint#842. Symptom: RuntimeError: dictionary keys changed during iteration.

[loriab]

Update: the relevant PR got merged to pint, and the 0.10 release is planned for 3/4 Jan. So two obstacles to py38 down (pydantic on mac on c-f and pint), and we'll see what pops up next.

[loriab]

A conda env with python 3.8 and qcelemental 0.12 is installable and works. Note that the pint 0.10 constraint (for python 3.8) isn't baked into the package, so it is possible to create a qcel0.12/py3.8/pint0.9 environment that won't work. We'll fix this up by 0.13.