upgrade typing_extensions version requirement

[mayk0gan]

Taken from requirements.txt: typing_extensions>=3.7.4.1,<4.0.0.0; python_version < "3.8".

This requirement doesn't allow us to use this project in our codebase as many packages already upgraded the requirement of this package to version >4.0.0 (botocore-stubs, aioitertools, and so on).
It also requires from spaCy for example to use the same requirement.

Is there any plan to upgrade it?

[adrianeboyd]

We still have to do some more testing to be sure, but it looks like we should be able extend this to <4.2.0.

[adrianeboyd]

This was addressed in v8.0.17.