[v24.x backport] repl: keep reference count for `process.on('newListener')` by addaleax · Pull Request #63194 · nodejs/node

When investigating a memory leak in one of our applications,
we discovered that this listener holds on to a `REPLServer`
instance and all heap objects transitively kept alive by it
by capturing as part of its closure.

It's cleaner to declare the listener outside of the `REPLServer`
class and to actually clean it up properly when it is no longer
required or meaningful, which is easily achieved through
keeping a reference count.

PR-URL: nodejs#61895
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>