doc: remove misleading paragraph about the Legacy URL API

The Legacy URL API is deprecated, see:

- https://nodejs.org/api/url.html#url_legacy_url_api
- https://nodejs.org/api/deprecations.html#
deprecations_dep0116_legacy_url_api

PR-URL: #29844
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <minwoo@nodesource.com>

doc/api/url.md

@@ -21,10 +21,6 @@ The `url` module provides two APIs for working with URLs: a legacy API that is
 Node.js specific, and a newer API that implements the same
 [WHATWG URL Standard][] used by web browsers.
 
-While the Legacy API has not been deprecated, it is maintained solely for
-backwards compatibility with existing applications. New application code
-should use the WHATWG API.
-
 A comparison between the WHATWG and Legacy APIs is provided below. Above the URL
 `'http://user:pass@sub.example.com:8080/p/a/t/h?query=string#hash'`, properties
 of an object returned by the legacy `url.parse()` are shown. Below it are