[TrigByteStreamCnvSvc] Add a check for valid CTP ROB fragment in TrigByteStreamInputSvc::nextEvent()

The CTP fragment is required to start processing an event in any meaningful HLT configuration. Since it is required even before we start running any algorithms, add a check in the InputSvc where we retrieve a new event from a data source, that we can retrieve the CTP fragment. If that's not the case, or the fragment has errors, it means the data source is corrupted and the job should fail.

The check is optional and disabled by default in C++ but enabled by default in the central python configuration of the service.

Closes ATR-25217

FYI @wiedenma