doc: clarify text about process not responding

The existing text about processes not responding is unclear, at least to
me. Suggestions for clarification welcome, but I think the best thing
might be to state that the process may stop responding and leave it at
that. The explanantion (about asynchronous listeners) is not clear to
me. (Why would the fact that the listeners are asynchronous matter?) If
it's an unnecessary detail (as seems likely), let's remove it.

PR-URL: https://github.com/nodejs/node/pull/36117


Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>