This isn't strictly necessary, this is just artifacts of the upgrade
process I did—and I figure may as well leave them here to help me in
the future if I need to do it again!
I'm not done with this yet, because I don't actually totally know how to upgrade the Postgres database files?
I could potentially just reset, since I don't care a *ton* about historical data, but I'll try to learn how `pg_upgrade` works in the context of Docker.
