Use Trusted Publishing to upload to PyPI

[nsoranzo]

I'm looking at reducing the risk of supply chain attacks on my project, which has temporalio as a dependency.
For details, see https://pydevtools.com/handbook/explanation/why-use-trusted-publishing-for-pypi/

[tconley1428]

Yes, thank you. We're aware of this and have it as a near term item to do, but we need to overhaul our release process somewhat to do so, so there is some work involved. I'll leave the item open to track.

[nsoranzo]

Fixed by #1575 .