src: update v8::Object::GetPropertyNames() usage

Use the non-deprecated version of GetPropertyNames().

PR-URL: https://github.com/nodejs/node/pull/23660


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>