Run CI checks on Python 3.9 and Python 3.10

[U8NWXD]

Expand supported Python versions to include versions 3.9 and 3.10

[1fish2]

LGTM.

I assume you'll push the install_requires numpy>=1.22.1 and scipy>=1.7.3 through to vivarium-ecoli. Or is it too aggressive to push these install_requires on all vivarium clients?

Since Python 3.10 deprecates distutils, we should plan to replace distutils in all vivarium projects. setuptools embeds a forked (and updated?) copy of distutils but there are compatibility issues. It's a mess.

(Presumably wcEcoli will stay on Python 3.8.7 and distutils. I did try updating it to setuptools but reverted that due to CovertLab/wcEcoli#1113.)

vivarium-core should consider using something more modern like Flit. Experts recommend Flit, and that should be easier and more robust to use and maintain. Flit handles the normal cases with a small, declarative pyproject.toml file instead of setup.py. setup.py is not dead but apparently we should not run it directly.

Flit does not support Cython code so it won't work for vivarium-ecoli. Given that, maybe we should learn and use a different tool everywhere like maybe Pipenv or Bento or something. AIUI, Numpy & Scipy are moving to Meson which is a build tool, not a packaging tool. Maybe it includes Python packaging features. Anyway, don't switch to numpy.distutils.