Raise node disconnected even if the transport is stopped

during the stop process, we raise network disconnect, so it is valid to raise then while we are in stop mode, and actually, we should not miss any events in such a case.
Typically, this is not a problem, since its during the normal shutdown process on the JVM, but when running a reused cluster within the JVM (like in our test infra with the shared cluster), we should properly raise those node disconnects