doc: fix url example to match behavior

Fixes one WHATWG URL example to match the actual behavior.

PR-URL: #23359
Fixes: #22653
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

doc/api/url.md

@@ -1269,7 +1269,7 @@ const myURL = new URL('https://%CF%80.example.com/foo');
 console.log(myURL.href);
 // Prints https://xn--1xa.example.com/foo
 console.log(myURL.origin);
-// Prints https://π.example.com
+// Prints https://xn--1xa.example.com
 ```
 
 [`Error`]: errors.html#errors_class_error