Add a new line after the guard statement to be compatible with the style guide.

app/controllers/projects/forks_controller.rb

@@ -30,6 +30,7 @@ class Projects::ForksController < Projects::ApplicationController
   def new
     return authenticate_user! unless current_user
+
     @namespaces = current_user.manageable_namespaces
     @namespaces.delete(@project.namespace)
   end