Idk a clear and concise way to group all these together, *and* include
`rspec-rails` in both development and test as the install instructions
recommend, but omit `webmock` from development.
Not that it matters a lot, I just want to be minimal about the gems we
include, for the sake of clarity.
This formulation is a bit verbose, but I think it's maximally clear and
self-consistent, and I appreciate that. I might change my mind later
though?
Anyway, I mostly just noticed this because of the redundancy where
`webmock`'s `group: :test` I think doesn't do anything? Shrug