Refactor Cache-Control and Vary definitions (#24347)

app/controllers/statuses_cleanup_controller.rb

@@ -6,6 +6,7 @@ class StatusesCleanupController < ApplicationController
   before_action :authenticate_user!
   before_action :set_policy
   before_action :set_body_classes
+  before_action :set_cache_headers
 
   def show; end
 
@@ -36,4 +37,8 @@ class StatusesCleanupController < ApplicationController
   def set_body_classes
     @body_classes = 'admin'
   end
+
+  def set_cache_headers
+    response.cache_control.replace(private: true, no_store: true)
+  end
 end