Notice that the fix was to use "Schrödinger’s Cat" instead of "Schrödinger's Cat". The fix was removing the single quote, as the script checked if there were characters that would run afoul of string escaping. The problem as it is has nothing to do with Unicode and was actually fixed by using a Unicode character.
That doesn't mean that there aren't any Unicode bugs in other tools, but that wasn't the issue in this particular case.