async function destroy(selector) {
  const calendar = await db.Calendar.findOne({
    where: {
      selector,
    },
  });

  if (calendar === null) {
    throw new NotFoundError('Calendar not found');
  }

  await calendar.destroy();
}
@description Delete a calendar.
@param {string} selector - Calendar selector.
@example
gladys.calendar.destroy('my-calendar');