input: Write a python function to generate a hopscotch board with random numbers from 1 to 6.
  assert len(generate_hopscotch_board(5)) == 5
  assert all(1 <= num <= 6 for row in generate_hopscotch_board(5) for num in row)
  assert len(generate_hopscotch_board(3)) == 3
output: import random
  
  def generate_hopscotch_board(size):
      board = []
      for _ in range(size):
          row = [random.randint(1, 6) for _ in range(3)]
          board.append(row)
      return board