The OpenAPI document describes an issue's and pull's assignee, an issue's labels, teams and dependencies, and making an issue private #5768

Done looks like:

• [ ] src/contract/openapi.ts describes PUT …/issues/{n}/assignee, PUT …/pulls/{n}/assignee, PUT …/issues/{n}/labels, GET and PUT …/issues/{n}/teams, GET …/issues/{n}/dependencies and POST …/issues/{n}/private, with bodies, answers and refusals as the routes give them.
• [ ] Those seven entries leave NOT_YET_DESCRIBED in test/openapi-coverage.test.ts, and the OpenAPI tests pass.
• [ ] Not a pull's labels (#5383) or confirming a wait (#5115).

Files: src/contract/openapi.ts, test/openapi-coverage.test.ts. Risks: delete only these lines from the shared list.