[Possible Schema Inaccuracy] multiple PR fields have odd description

[xmo-odoo]

I'm not entirely sure that these are schema inaccuracies but multiple fields of PRs (specifically the "pull-request" response / schema) have an odd definition:

• mergeable is a nullable boolean field,it is not otherwise documented, it's hard to fathom why a PR would be something other than "mergeable" and "not mergeable". Either the field should be marked required, or the behaviour should be explained (I guess "we don't know if it's mergeable yet" is possible but in that case why not just set it to non-mergeable?).
• draft is somewhat similarly an optional boolean, it's not clear when it would be absent (possibly projects which don't support / allow draft PRs? still why have that in the response rather than just false?)
• rebaseable is both nullable and optional, same remarks as above.
• mergeable_state is completely undocumented aside from knowing it's a string. Looking at the GraphQL API, it the example value ("clean") matches the MergeStateStatus enum. If this is the right conversion, mergeable_state should be defined as an enum with those values provided (and documented as they are in the graphql schema, maybe).

[nickfloyd]

Please let us know if this work is still needed. We're trying to follow up on any older issues to make sure they get properly routed.

[xmo-odoo]

Please let us know if this work is still needed. We're trying to follow up on any older issues to make sure they get properly routed.

As far as I can tell none of the reported considerations have been touched since. I removed the bit about array fields as I apparently reported them again a few years later (#3501).