Oh this was a fun little dev environment bug: I ran `public_data:pull`
on my laptop before migrating my database, so the `items` table pulled
as the latest production version, which included the migrations, but
they hadn't been marked as "run" yet.
So Rails was still telling me I needed to run them, but the migrations
themselves were crashing, with stuff like "there's already a column
with this name!"
This change ensures that `public_data:pull` won't run until migrations
are done, to prevent silly accidents like that.