url: remove unused kFormat from url

Author: anonrig

lib/internal/url.js

@@ -100,7 +100,6 @@ const FORWARD_SLASH = /\//g;
 
 const context = Symbol('context');
 const searchParams = Symbol('query');
-const kFormat = Symbol('format');
 
 const updateActions = {
  kProtocol: 0,
@@ -794,7 +793,6 @@ class URL {
 }
 
 ObjectDefineProperties(URL.prototype, {
- [kFormat]: { __proto__: null, configurable: false, writable: false },
  [SymbolToStringTag]: { __proto__: null, configurable: true, value: 'URL' },
  toString: kEnumerableProperty,
  href: kEnumerableProperty,