Fix settings pages being cacheable by the browser (#12714)

Fix #12255

app/controllers/settings/base_controller.rb

@@ -2,10 +2,15 @@
 
 class Settings::BaseController < ApplicationController
   before_action :set_body_classes
+  before_action :set_cache_headers
 
   private
 
   def set_body_classes
     @body_classes = 'admin'
   end
+
+  def set_cache_headers
+    response.headers['Cache-Control'] = 'no-cache, no-store, max-age=0, must-revalidate'
+  end
 end