fixed url to console component

examples/ethernet/iperf/README.md

@@ -9,7 +9,7 @@
 
 This example demonstrates basic usage of [iperf](https://iperf.fr/) protocol to measure the throughout/bandwidth of Ethernet.
 
-The cli environment in the example is based on the [console component](https://docs.espressif.com/projects/esp-idf/en/latest/api-guides/console.html).
+The cli environment in the example is based on the [console component](https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/system/console.html).
 
 ## How to use example