[Futurev4] fix failing tests

• Test 1: GaussSys.gausssys Here, I had to change the test so that it accepts the minimum working configuration coming from Gaussino.
• Test 2: LoKiGen.jira_461 ROOTIO from HepMC3 caused namespace collision with HepMC. It'll be now commented out in Gaussino as there is no need for it yet.
• Test 3: LoKiGen.lokigen0 Same problem as above + it looks like LoKi has some problems with dereferencing HepMC.GenParticle(). For example, this GP(HepMC.GenParticle()) gives

static double LoKi::Dicts::FunCalls<HepMC3::GenParticle>::__call__(LoKi::Functor<shared_ptr<const HepMC3::GenParticle>,double>& fun, const shared_ptr<const HepMC3::GenParticle>& o) =>
    could not convert argument 2

• Test 4: GaussTracker.shortened_sensdet_name This test, in its current shape, won't work because the expected debug debug() << "Sens det shortened name " << name() << " -> " << detname << endmsg; has been moved to the construct() in GiGaMTG4SensDetFactory. I wonder, in fact, whether this test is going to be useful... update: This is a very specific configuration in order to trigger a debug message with a shortened name of the sensitive detector. In order to do so, in Gauss-on-Gaussino it will only be triggered by running construct() on the GiGaSensDetTracker.

needs Gaussino/Gaussino!18 (merged) @gcorti @dmuller

GaussSys/tests/options/testGaussSys-30000000.py

+###############################################################################
+# (c) Copyright 2021 CERN for the benefit of the LHCb Collaboration           #
+#                                                                             #
+# This software is distributed under the terms of the GNU General Public      #
+# Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING".   #
+#                                                                             #
+# In applying this licence, CERN does not waive the privileges and immunities #
+# granted to it by virtue of its status as an Intergovernmental Organization  #
+# or submit itself to any jurisdiction.                                       #
+###############################################################################
+from Configurables import Generation
+Generation().EventType = 30000000
+from Gaussino.Generation import GenPhase
+GenPhase().SampleGenerationTool = "MinimumBias"
+GenPhase().ProductionTool = "Pythia8Production"
+from Configurables import ToolSvc
+from Configurables import EvtGenDecay
+ToolSvc().addTool( EvtGenDecay )
+ToolSvc().EvtGenDecay.UserDecayFile = "$DECFILESROOT/dkfiles/minbias.dec"