util: fix proxy inspection

This prevents any proxy traps from being called while inspecting
proxy objects. That guarantees a side-effect free way of inspecting
proxies.

PR-URL: https://github.com/nodejs/node/pull/26241
Fixes: https://github.com/nodejs/node/issues/10731
Fixes: https://github.com/nodejs/node/issues/26231
Refs: https://github.com/nodejs/node/issues/25212
Refs: https://github.com/nodejs/node/issues/24765


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>