Fix ESLint parse error: use property access instead of destructuring

The project's ESLint config has no ecmaVersion set, which defaults to ES5.
Destructuring syntax is ES6+, so replace with a simple property access.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: danmactough

lib/utils.js

@@ -1,4 +1,4 @@
-var { URL: WHATWGURL } = require('url')
+var WHATWGURL = require('url').URL
   , namespaces = require('./namespaces')
   ;