fix the failing spec

don't fallback on the upstream project if the project isn't a fork.

ee/app/controllers/ee/projects/merge_requests/application_controller.rb

@@ -36,9 +36,11 @@ module EE
         def clamp_approvals_before_merge(mr_params)
           return mr_params unless mr_params[:approvals_before_merge]
 
+          # target the MR target project in priority, else it depends wether the project
+          # is forked.
           target_project = if @merge_request
                              @merge_request.target_project
-                           elsif @project.id.to_s != mr_params[:target_project_id]
+                           elsif @project.forked? && @project.id.to_s != mr_params[:target_project_id]
                              @project.forked_from_project
                            else
                              @project