src: add missing option parser template for the DebugOptionsParser

This allows embedders to run `node::options_parser::Parse` for a
`node::DebugOptions`.

PR-URL: https://github.com/nodejs/node/pull/28543


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Eugene Ostroukhov <eostroukhov@google.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>