chore: fix link error (#828)

Signed-off-by: rogerogers <[email protected]>

Author: rogerogers

content/en/docs/hertz/tutorials/observability/tracing.md

@@ -4,7 +4,6 @@ linkTitle: "Tracing"
 weight: 2
 keywords: ["Tracing"]
 description: "Hertz provides tracing capabilities."
-
 ---
 
 In microservices, link tracing is a very important capability, which plays an important role in quickly locating problems, analyzing business bottlenecks, and restoring the link status of a request. Hertz provides the capability of link tracking and also supports user-defined link tracking.
@@ -62,6 +61,6 @@ The above information is available at Finish
 
 At the same time, if you don't want to log this information, you don't have to register any tracer, and the framework stops logging this information.
 
-An extension for opentracing is provided in hertz-contrib, and a [demo]((https://github.com/cloudwego/hertz-examples/tree/main/tracer)) for calling from http to rpc is also available in hertz-examples.
+An extension for opentracing is provided in hertz-contrib, and a demo for calling from http to rpc is also available in [hertz-examples](https://github.com/cloudwego/hertz-examples/tree/main/tracer).
 
 Related Repository： https://github.com/hertz-contrib/tracer

content/zh/docs/hertz/tutorials/observability/tracing.md

@@ -62,5 +62,5 @@ WriteFinish        = newEvent(writeFinish, LevelDetailed) // 写 response 结束
 
 同时，如果不希望记录这些信息，可以不注册任何 tracer，则框架停止对这些信息的记录。
 
-hertz-contrib 中提供了 opentracing 的扩展方式，也在 hertz-examples 提供了可以从 http 到 rpc 调用的 demo。
+hertz-contrib 中提供了 opentracing 的扩展方式，也在 [hertz-examples](https://github.com/cloudwego/hertz-examples/tree/main/tracer) 提供了可以从 http 到 rpc 调用的 demo。
 仓库：https://github.com/hertz-contrib/tracer