Fix link in documentation

PUBLISHED_FROM=d4337a442a8f5728826eb109bdca41ca03a18d2a

docs/http/client_example.md

@@ -43,4 +43,4 @@ int main(void) {
 }
 ```
 
-See full source code at [HTTP client example](https://github.com/cesanta/dev/tree/master/mongoose/examples/http_client).
+See full source code at [HTTP client example](https://github.com/cesanta/mongoose/tree/master/examples/http_client).