net: remove unused ObjectKeys

Co-authored-by: Luigi Pinca <luigipinca@gmail.com>

PR-URL: https://github.com/nodejs/node/pull/40344
Fixes: https://github.com/nodejs/node/issues/40336


Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Zijian Liu <lxxyxzj@gmail.com>
Reviewed-By: Robert Nagy <ronagy@icloud.com>