Drop uses of HepMC

We are planning to switch from HepMC2 to HepMC3 in the upcoming LCG 106 (see SPI-2591).

HepMC3 is not backward compatible and it's very complicated to port LHCb code to it, so it was decided to drop the uses of it everywhere else then simulation code.

This MR removes all code relying on HepMC and adapts some tests stdout exclusions to take into account that reading old MC files requires dictionaries that are not built anymore.

Goes with: Rec!4226 (merged) Allen!1862 (merged) Moore!4240 (merged) DaVinci!1223 (merged)