[#73389] Fix rubocop offenses

Removes unnecessary rubocop:disable and trailing blank line.

Author: myabc

modules/backlogs/app/controllers/agile/sprints_controller.rb

@@ -58,7 +58,7 @@ def create # rubocop:disable Metrics/AbcSize
       end
     end
 
-    def update # rubocop:disable Metrics/AbcSize
+    def update
       call = ::Sprints::UpdateService
         .new(user: current_user, model: @sprint)
         .call(attributes: agile_sprint_params[:sprint])

modules/backlogs/spec/controllers/rb_stories_controller_spec.rb

@@ -220,5 +220,4 @@
       end
     end
   end
-
 end