Add a few build artifacts to rake db:seed

So the basic concept here seems useful, and the code does work.

But before merging, I'd like some discussion about how many artifacts to make.

The patch as-is makes too few: it is really hard to find one clicking around the user interface.

The simplest answer is to just make one for every build attempt. Maybe that is the way to go, it just slows down rake db:seed even more than it is already.

Perhaps creating just a handful, but making them for the attempts which are easiest to navigate to, would work?

@square/kochiku-contributors