NEXUS-6027: Rework of 5b8963aa7b482aa307e15eaef0697d8d7fcce349

The 5b8963aa7b482aa307e15eaef0697d8d7fcce349 fix was not correct,
as in some UTs it tried to start/stop twice the host.

This is simpler, just in this one single UT is nx started
to leave out the change in superclass that would affect
all UTs