mail_settings: {
      sandbox_mode: {
          enable: process.env.NODE_ENV === 'test',
      },
  }

const msg =  {
      to: email,
      from: EMAIL_FROM,
      subject,
      replyTo: REPLY_TO,
      dynamicTemplateData,
      templateId,
      mail_settings: {
          sandbox_mode: {
              enable: process.env.NODE_ENV === 'test',
          },
      }
  };
  sgMail.send(msg)