opentelemetry-stdout-tree:OpenTelemetry跨度导出器，以树状格式打印迹线

开放遥测标准输出树 的stdout导出器实现，以树状格式打印迹线。 SE my-awesome-books.com GET /authors/:authorId/books/:bookId 500 584ms ================== IN middleware - expressInit 0 0 = IN middleware - query 0 0 = IN middleware - session 0 523ms ==============