Reconcile out discrepancy between master and main branch

[mradamcox]

At some point in this repository's history, a main branch was created to become the new default. However, the old default, master still exists and when I preview a pull request from the old master into the new main there is a long list of commits that would be applied. I doubt we should actually be applying all of these commits, but I would like to look through them to figure out what they contain, and, if relevant, use git cherry-pick to pull them into main.

Ultimately, the master branch should be deleted.