function generateRandomDateTuple() {
  const date = new Date(Math.random() * (MAX_DATE - MIN_DATE) + MIN_DATE);
  return [date.getFullYear(), date.getMonth() + 1, date.getDate()];
}
Generate a random date.

@return {[number, number, number]} Year as an integer, month as an
  integer >= 1 and <= 12, day as an integer >= 1.