Remove line_items resource from routes.rb
Remove line_items resource from routes.rb

Hey,
It looks like this one line `resources :line_items` is unnecessary, there is no `line_items_controller.rb` in backend part.

Fixes #6211

keatonrow/spree,azclick/spree,keatonrow/spree,keatonrow/spree,azclick/spree,azclick/spree,keatonrow/spree,azclick/spree