Convert release.sh from bash to python [part 1]

[wisechengyi]

Convert list_prebuilt_wheels and fetch_prebuilt_wheels to python.

Same logic + parallel downloading in python.

For #5551

[wisechengyi]

This is ready for review. Thanks.

[Eric-Arellano]

While I don't know the whole context, this looks like a great project! Python scripts are much easier to maintain and extend than Bash.

[baroquebobcat]

Thanks for this.

Wow, fire looks really cool!

[jsirois]

I'm all in favor of converting release to a language we can reasonably test, so I won't block. That said - this is all a bit simpler perhaps on the prod side using boto3, but definitely on the testing side using moto. Consider tests in a follow-up, and when doing so, consider switching to boto since it does support parallel transfers and convenient testing via moto.

[wisechengyi]

Thanks for the recs, John!

[wisechengyi]

Going to land this by EOD if there is no further comments.

[stuhood]

Thanks Yi!