Use keyword arguments in tests

Raisl 5.1 removes support for non-keyword arguments in `#process`,
`#get`, `#post`, `#patch`, `#put`, `#delete`, and `#head` for the
`ActionDispatch::IntegrationTest` and `ActionController::TestCase`
classes. This means we have to add `params` everywhere in the controller
tests.

spec/controllers/schedules_controller_spec.rb

@@ -13,7 +13,7 @@ describe SchedulesController do
         create(:event_scheduled, program: conference.program)
         create(:event_scheduled, program: conference.program)
 
-        get :show, conference_id: conference.short_title, format: :xml
+        get :show, params: { conference_id: conference.short_title, format: :xml }
       end
 
       it 'assigns variables' do