Fix GiGaMTRunManager not terminating run
The problem is that we had an implementation of GiGaMTRunManager::RunTermination
that was never run. For example, it was not possible to call EndOfRunAction
s. The solution is:
- to simplify the code as much as possible by reusing the code from Geant4 that does not touch the management of the event loop
- explicitly call it from the
GiGaMT::finalize
before deleting the run manager