[Rails5] Fix pipeline_schedules_controller_spec

In Rails 5.0 there's a bug [1] in controller tests that doesn't parse
nested parameters correctly.

This commit brings a workaround to make specs work again both in rails4
and rails5.

[1]: https://github.com/rails/rails/issues/23997

changelogs/unreleased/blackst0ne-rails5-fix-pipeline-schedules-controller-spec.yml

+---
+title: "[Rails5] Fix pipeline_schedules_controller_spec"
+merge_request: 19919
+author: "@blackst0ne"
+type: fixed

spec/controllers/projects/pipeline_schedules_controller_spec.rb

@@ -310,11 +310,21 @@ describe Projects::PipelineSchedulesController do
     end
 
     def go
+      if Gitlab.rails5?
+        put :update, params: { namespace_id: project.namespace.to_param,
+                               project_id: project,
+                               id: pipeline_schedule,
+                               schedule: schedule },
+                     as: :html
+
+      else
         put :update, namespace_id: project.namespace.to_param,
-                   project_id: project, id: pipeline_schedule,
+                     project_id: project,
+                     id: pipeline_schedule,
                      schedule: schedule
       end
     end
+  end
 
   describe 'GET #edit' do
     describe 'functionality' do