Add GitHub workflow to make sure history fields docs are up-to-date

We have documentation pages for [no-FATES](https://escomp.github.io/CTSM/users_guide/setting-up-and-running-a-case/history_fields_nofates.html) and [FATES](https://escomp.github.io/CTSM/users_guide/setting-up-and-running-a-case/history_fields_fates.html) setups that describe all our history outputs. The source files for these are / can be generated by tests (see #2516). It would be great to have a GitHub Workflow that would do very short single-point runs to generate those files, then compare them to the files in `doc/source/` and fail on any diffs. This would realistically require the use of a container in which to do the runs, which I'm hoping to make as part of my CIRRUS CI work.

This might also allow us to remove the `clm/extra_outputs` test referenced in #2516 and then close that issue.