Remove js handler from Profiles#update

It was only used for the appearance live updating, which is now handled
by Profiles::Preferences#update

app/controllers/profiles_controller.rb

@@ -26,7 +26,6 @@ class ProfilesController < Profiles::ApplicationController
     respond_to do |format|
       format.html { redirect_to :back }
-      format.js
     end
   end