[rails] Only set Date headers if not created by servers

Author: p8

frameworks/Ruby/rails/app/controllers/application_controller.rb

@@ -1,11 +1,13 @@
 # frozen_string_literal: true
 
 class ApplicationController < ActionController::Base
-  before_action :add_header
+  if defined?(Agoo) || defined?(Falcon) || defined?(Puma)
+    before_action :add_date_header
+  end
 
   private
 
-  def add_header
+  def add_date_header
     response.set_header('Date', Time.now.httpdate)
   end
 end