code: public function button($text, $buttons)
      {
          $payload = [
              'template_type' => 'button',
              'text' => $text,
              'buttons' => $buttons,
          ];
  
          $this->setAttachment('template', $payload);
  
          return $this;
      }
docs: Populate button
  
  @param string $text Text
  @param array $buttons Buttons
  
  @return Message