Modify PyPI wheel generation to use Trusted Publisher

PyPI's preferred way to upload wheels is their Trusted Publisher method. From their website: "PyPI package maintainers can adopt a new, more secure publishing method that does not require long-lived passwords or API tokens to be shared with external systems."

https://blog.pypi.org/posts/2023-04-20-introducing-trusted-publishers/

We should update OCIO to use this method.