These feature tests were taking too long, we can't run them for every
single model.
I'm taking the approach of using one different model for each test, but
in theory only using a few models covering every possible scenario
would be enough.
The `type: :feature` is automatically detected by RSpec because these
tests are inside the `spec/features` folder. Using `feature` re-adds a
`type: :feature` to these files, which will result in a conflict when we
upgrade to Rails 5.1's system tests.
Because of this change, we also need to change `background` to `before`
or else these tests will fail.
