Fix ATS does not honor proxy.config.body_factory.response_max_size

Author: shinya1020

proxy/http/HttpTransact.cc

@@ -7979,9 +7979,9 @@ HttpTransact::build_error_response(State *s, HTTPStatus status_code, const char
   int64_t len;
   char *new_msg;
 
-  new_msg = body_factory->fabricate_with_old_api(error_body_type, s, 8192, &len, body_language, sizeof(body_language), body_type,
-                                                 sizeof(body_type), s->internal_msg_buffer_size,
-                                                 s->internal_msg_buffer_size ? s->internal_msg_buffer : nullptr);
+  new_msg = body_factory->fabricate_with_old_api(
+    error_body_type, s, s->http_config_param->body_factory_response_max_size, &len, body_language, sizeof(body_language), body_type,
+    sizeof(body_type), s->internal_msg_buffer_size, s->internal_msg_buffer_size ? s->internal_msg_buffer : nullptr);
 
   // After the body factory is called, a new "body" is allocated, and we must replace it. It is
   // unfortunate that there's no way to avoid this fabrication even when there is no substitutions...