src: use MaybeLocal.ToLocal instead of IsEmpty worker

This commit suggest using MaybeLocal.ToLocal and passing in the
Local<String> node_opts. It also introduces a variable, arg_v8, of type
Local<String> to enable the use of ToLocal.

The motivation for doing this is that the following
MaybeLocal::ToLocalChecked and MaybeLocal::FromMaybe calls can then be
avoided.

PR-URL: https://github.com/nodejs/node/pull/33599


Reviewed-By: Zeyu Yang <himself65@outlook.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>