doc: edit deprecation identifier info in Collaborator Guide

Edit the deprecation identifier material in the Collaborator Guide for
simplicity and clarity.

PR-URL: https://github.com/nodejs/node/pull/26372


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>