Generator doesn't honor Python 3 minor versions using typing.io imports

[PeterTillema]

When you run "Generate ANTLR Recognizer..." the lexer output file has

from typing.io import TextIO

in its header, while doing it yourself yields

if sys.version_info[1] > 5:
	from typing import TextIO
else:
	from typing.io import TextIO

The upper one is clearly wrong, as it's dependent on the minor version of Python 3.

[bjansen]

This looks like a different version between what's shipped in the plugin and what you're using when you generate the parser yourself. The header you're mentioning was introduced in february and released in ANTLR 4.9.2 according to GitHub.
The IntelliJ plugin is still shipping ANTLR 4.9.1, I'll prepare a new version with the latest ANTLR.