Remove humanfriendly

[srittau]

https://github.com/xolox/python-humanfriendly

The last commit was in September 2021 and it doesn't work with Python 3.13. The last change specific to our humanfriendly stubs was in December 2022, after that it was just general maintenance. The stubs are marked as "complete" and are in a good place, I think this is a good time to end support in typeshed.

[sobolevn]

When will be the end date for the support? 6 months from now?

[srittau]

It can be removed now, unless you want to keep it for a reason?

[sobolevn]

Nope, just asking :)