assert: handle errors properly with deep*Equal

PR-URL: https://github.com/nodejs/node/pull/15001


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>