code: public function serialize(Message $message, array $options = [])
      {
          if (!isset($options['yaml_inline'])) {
              $options['yaml_inline'] = 3;
          }
  
          if (!isset($options['yaml_indent'])) {
              $options['yaml_indent'] = 2;
          }
  
          return Yaml::dump(
              parent::serialize($message, $options),
              (int) $options['yaml_inline'],
              (int) $options['yaml_indent']
          );
      }
docs: {@inheritdoc}
  
  Note that the greater the yaml_inline option the slower it is.
  3 provides really good human readability but if you need
  speed use 0 or 1.