It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
ATM it only implements server side of it, as my need is for automation purposes. However it should probably be added in the UI too as it's unexpected to have pinned_until and no bannered_until.