input: Write a python function to convert a list of strings to a list of integers.
  assert convert_list_integers(['12', '14', '17', '25', '99', '168']) == [12, 14, 17, 25, 99, 168]
  assert convert_list_integers(['1', '2', '3']) == [1, 2, 3]
  assert convert_list_integers(['10', '20', '30']) == [10, 20, 30]
output: def convert_list_integers(lst):
      return [int(i) for i in lst]