Upgrading sphinx to bipass logging problems

[john-science]

Description

In an effort to reduce the strain of people trying to create their own ARMI-adjacent docs, this PR upgrades the version of Sphinx we are using from 2.2.0 to 4.4.0. It also implements some important future-proofing against Python's continuous changes to the standard library method logging.Logger.log(). These changes together allow us to remove a bunch of calls to logging.setLoggerClass(), that were causing people trouble.

As part of my testing, I had GitHub Actions build these docs in Python 3.7, 3.8, and 3.9. And I verified that my changes to runLog.py and the docs dependencies work in all versions.

NOTE: Please do not Merge this PR!
NOTE: Please let John Merge this PR!
NOTE: John needs time to update downstream build systems before this PR is Merged!

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Checklist

• Tests have been added/updated to verify that the new or changed code works.
• Docstrings were included and updated as necessary
• The code is understandable and maintainable to people beyond the author
• There is no commented out code in this PR.

If user exposed functionality was added/changed:

• Documentation added/updated in the doc folder.
• New or updated dependencies have been added to setup.py.

[john-science]

@jakehader @drewejohnson This PR is in reference to Issue #518

[john-science]

@ntouran There are some minor visual differences in the resultant docs, that I could see. Hopefully I didn't miss anything. We don't really have an SOP for when we make massive changes to the docs, to make sure everyone still likes the way they look. Hmm.

I had to exactly pin the versions of these three libraries in order for the built docs to look right:

• sphinx-gallery==0.9.0
• sphinx-rtd-theme==0.5.2
• sphinxcontrib-apidoc==0.3.0

[ntouran]

approved with one simple comment