input: Write a python function to generate an array of specified size with random integers between 0 and 100 using numpy.
  assert len(generate_random_array(10)) == 10
  assert isinstance(generate_random_array(5), np.ndarray)
  assert all(0 <= x < 100 for x in generate_random_array(20))
output: import numpy as np
  
  def generate_random_array(size):
      return np.random.randint(0, 100, size)