evaluate leveraging GitHub's official openapi schema for type validation

[softprops]

💡 Feature description

The current types in this crate were derived from GitHub's documentation and from usage in practice. The combination of these resulted in some guess work. GitHub has published a formal openapi schema which should remove some of that guesswork https://github.blog/2020-07-27-introducing-githubs-openapi-description/

Let's evaluate what we can leverage the canonical information to produce a more correct crate where guesses were wrong

💻 Basic example