input: Write a python function to remove specified characters from a string.
  assert remove_char_from_string("computer science", "c") == "omputer siene"
  assert remove_char_from_string("hello world", "l") == "heo word"
  assert remove_char_from_string("data science", "a") == "dt science"
output: def remove_char_from_string(s: str, char: str) -> str:
      return s.replace(char, '')