Remove role color highlighting from custom css (#33493)

app/controllers/custom_css_controller.rb

@@ -1,8 +1,6 @@
 # frozen_string_literal: true
 
 class CustomCssController < ActionController::Base # rubocop:disable Rails/ApplicationController
-  before_action :set_user_roles
-
   def show
     expires_in 3.minutes, public: true
     render content_type: 'text/css'
@@ -14,8 +12,4 @@ class CustomCssController < ActionController::Base # rubocop:disable Rails/Appli
     Setting.custom_css
   end
   helper_method :custom_css_styles
-
-  def set_user_roles
-    @user_roles = UserRole.providing_styles
-  end
 end