let clickable = true;

const callback = (event) => {

  if (!clickable) {
    return;
  }

  (중략)
  if (turn === 'X') {
    const emptyCells = rows.flat().filter((v) => !v.textContent);
    const randomCell = emptyCells[Math.floor(Math.random() * emptyCells.length)];

    clickable = false;
    setTimeout(() => {

      randomCell.textContent = 'X';
      checkWinnerAndDraw(randomCell);

      clickable = true;
    }, 1000);

  }
};