Fix for partial recompilation of Simulation/AtlasGeant4 (ATLASSIM-6196)
When using VecGeom::vecgeom in:
We missed adding
find_package( Geant4 ${_quietFlag} )
to the PreConfig.cmake
files for the Athena and AthSimulation projects.
https://gitlab.cern.ch/atlas/athena/-/blob/master/Projects/Athena/cmake/PreConfig.cmake.in#L40
https://gitlab.cern.ch/atlas/athena/-/blob/master/Projects/AthSimulation/cmake/PreConfig.cmake.in#L29
Adding these lines should fix ATLASSIM-6196.
(Committing on behalf of @akraszna)