def set_tags(tags)
      return unless tags.is_a?(Hash)
      tags.each do |k,v|
        set_tag(k, v)
      end
      self
    end
def set_tags(tags)
      return unless tags.is_a?(Hash)
      tags.each do |k,v|
        set_tag(k, v)
      end
      self
    end
Helper method to add multiple tags to this span

 @params tags [Hash]
 @return [Span]