Oh I didn't realize the lowest version Rails had for this is 4.2. I wish running `rake db:migrate` checked this, but I'm running into it on another branch when I try to create a *new* migration which for some reason leads it to inspect the old migrations and notice the issue. Weird!
I'm not sure it's literally true that they were all built against Rails 3.2, but that's what it was at before we upgraded, and like. that's probably fine
