Trailing spaces on blank lines results in error

[RichDom2185]

[Transferred from source-academy/js-slang/issues/1412]

When running Python 1, Having trailing spaces on otherwise blank lines results in errors:

• When number of spaces is a multiple of 4: GenericUnexpectedSyntaxError
• Otherwise, NonFourIndentError

Example:

print("hi")

print("world")

Not sure if this is intentional.

[Fidget-Spinner]

Fixed by https://github.com/source-academy/py-slang/commit/1587bd56d80efdc061bdae7ce8b364e7f06a7284.

To reflect the fix in js-slang, we need to git submodule update --remote