Switch over to full GraphQL

[lilyminium]

Fixes #370, I think.

This PR stops using PyGithub entirely and switches over to using GraphQL directly. It's not strictly necessary since the only issue with PyGithub was to do with projects, but as the project card objects are passed into every state-update function, I only realized this after rewriting the whole thing. The main overhead added is that we now use the GraphQL API to add/remove labels, get files, and add comments. If this is too much maintenance overhead I can try to smush together this PR and #375.

The new code is in lifecycle-v2.py. I added a test CI that runs through some steps (e.g. adding/removing labels, adding comments, moving cards around) that should only trigger on PRs labelled with test-ci. That's what's repsonsible for the mess here and in #375.

[openff-dangerbot]

This is a test comment from running CI. Please ignore

[openff-dangerbot]

This is a test comment from running CI. Please ignore

[openff-dangerbot]

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[openff-dangerbot]

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[openff-dangerbot]

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[j-wags]

Thanks for taking a stab at this. I guess I see two paths forward here:

• Fix this ourselves in the short term, with a mix of manual intervention and direct graphql-based automation
• Wait for pygithub to update to the new project board interface

Given that this repo has no (/few?) tests, that replacing this functionality will add a lot of lines, and I don't know graphql beyond some stuff I hacked together in my last PR, I don't think I can meaningfully review this PR. But on the other hand, given that this only has internal consumers, that our previous QCA datasets are immutable, and that we can always roll things back (or wait for the pygithub update), I think it's fine to move ahead with this in the short term.

So feel free to merge this when you think it's good, and even merge things without my review/commit directly to master to avoid having to wait for my responses :-)