Utilities: Make the js REPL autocomplete correctly handle new Ident

Previously, `new` was being recognised as an identifier, which was
preventing this from working.

Userland/Utilities/js.cpp

@@ -1030,7 +1030,7 @@ int main(int argc, char** argv)
  case CompleteProperty:
  // something came after the property access, reset to initial
  case Initial:
- if (js_token.is_identifier_name()) {
+ if (js_token.type() == JS::TokenType::Identifier) {
  // ...<name>...
  mode = CompleteVariable;
  variable_name = js_token.value();