Nox `docs-build` Session Fails with ZoneInfo Error on Ubuntu

[natescherer]

Adding this mainly as doc in case anyone else runs into the issue: the docs-build nox session fails with the below error on Ubuntu:

ValueError: ZoneInfo keys may not be absolute paths, got: /UTC

I ran it down, and this is because of python-babel/babel#990

As a workaround in the meantime, you can change line 208 in noxfile.py to the below, which will pin doc build to Python 3.8, which is unaffected by the linked babel bug:

@session(name="docs-build", python=python_version"3.8")

Note that if you are running nox locally, you'll need to run without -r in order for the docs-build session to have its venv rebuilt.

[natescherer]

If anyone is running into this issue, there's a temporary kludge-y fix here until babel can be updated: python-babel/babel#990 (comment)