stream: add isDisturbed helper

Adds a helper util used to determine whether a stream has been
disturbed (read or cancelled).

Refs: https://github.com/nodejs/node/issues/39627

PR-URL: https://github.com/nodejs/node/pull/39628


Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>