Fix ssl related bug in xnf simulator

Fix ssl related bug in xnf simulator

Fix bug when xnf simnulator was using same SecurityKeys object instance for every new VesClient,
which resulted in fault while trying to connect to collector.

With new implementation simulator reuses same HvVesProdcuer from SDK
for every VesEvent request received and creates new Producer for every
WireFrameEvent request. This allows to continue testing cases in which
there is need to assert if connection was dropped from malicious client.

Change-Id: I5f51a58de85cccf7de6ab2392f86259502be31dd
Issue-ID: DCAEGEN2-1291
Signed-off-by: Jakub Dudycz <jakub.dudycz@nokia.com>
Signed-off-by: Filip Krzywka <filip.krzywka@nokia.com>