lib: refactor ERR_SYNTHETIC

- Tidy up description in docs.
- Remove a second definition in the docs.
- Remove unused string input parameter.
- Remove duplicate "JavaScript Callstack" in error messages.

PR-URL: https://github.com/nodejs/node/pull/25749


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>