更新 Issue。Update issue.

更新指定仓库中已有 Issue 的信息，包括标题、描述、状态、优先级等字段。支持部分更新，仅传入需要修改的字段即可。 Update an existing issue in the specified repository, including title, description, state, priority, and other fields. Supports partial updates; only pass the fields that need to be changed. state 和 state_reason 必须同时提供或同时不提供，否则会返回参数错误。 Note: state and state_reason must be provided together or omitted together, otherwise a parameter error will be returned. 修改状态时需指定合理的状态原因（如"已完成"或"不计划修复"）。调用者需具有仓库的写入权限或 Triage 角色。 When changing state, specify a valid state reason (e.g., "completed" or "not planned"). The caller must have write access or the Triage role. 访问令牌调用此接口需包含以下权限。Required permissions for access token. repo-issue:rw