Provide feedback for the upload api 2.0 draft

[konstin]

https://discuss.python.org/t/pep-694-upload-2-0-api-for-python-package-repositories/16879

https://peps.python.org/pep-0694/

https://twitter.com/dstufft/status/1541588782188826624

maturin will need to implement and use the new upload api, so we should provide feedback for the draft, maybe even try to implement it to see how well it harmonize with ureq