PerfMonComps: Updates to begin/end event handling in PerfMonSvc

This is a continuation of !36582 (merged). Since we've gotten rid of the Begin/EndEvent incidents and trigger these via certain components now, we always need the auditors. I also made the names of the components that trigger the begin/end event configurable. In serial Athena every event starts w/ an before execute auditor call from AthMasterSeq and ends w/ an after execute call from AthMasterSeq. However, in MT that's not the case. PerfMonSvc is still used for monitoring events w/ --nthreads=1. There, we simply use IncidentProcAlgs for this purpose.

Closes ATLASSIM-4839