update the way we upload to PyPI upon release

[tepickering]

PyPI now supports Trusted Publishing and we should take advantage of it in our release workflow. there is an officially supported action for this, gh-action-pypi-publish. the openastronomy reusable workflows don't support it yet, but here are instructions for how to work around that currently: https://github-actions-workflows.openastronomy.org/en/latest/trusted_publishing.html.

[hpparvi]

Thanks for the heads-up! I'll take a look into this.

[tepickering]

i saw something about this a while back, but forgot to post an issue. the openastronomy article reminded me...