ISF_FastCaloSimEvent: Fix test failure in dbg build.

TFCSSimulationState::Print was printing all arms of a union holding a number of fundamental types.

However, if one tries to access a something of bool type that holds something other than 0 or 1, then we'll get a warning from the UB sanitizer.

Further, if we print it as a char, it may well be non-printable, which can screw up a terminal.

So don't print as bool or char.