input: Write a python function to remove whitespaces from each string in a list.
  assert remove_whitespace(['Hello  World  ', 'Hi  there', 'Good  Morning']) == ['Hello  World', 'Hi  there', 'Good  Morning']
  assert remove_whitespace(['  Leading', 'Trailing  ', '  Both  ']) == ['Leading', 'Trailing', 'Both']
  assert remove_whitespace(['NoSpaces', '  ', '']) == ['NoSpaces', '', '']
output: def remove_whitespace(strings):
      return [s.strip() for s in strings]