JetTagCalibration: use AthMessaging and unique_ptr
There are two commits and two independent set of changes:
- There is a crazy amount of (unprotected!) DEBUG messages in
JetTagCalibCondDatathat showed up as part of ATR-21692. On top of it the code was creating a
MsgStreaminstance each time. That technique should really only be used for rare messages. Instead, change the code to inherit from
AthMessaging. But to be honest, the code would be a lot more readable if there wouldn't be almost one DEBUG message for each line of code...
unique_ptrfor BDTs and histograms to reflect the ownership. Also avoids custom cleanup methods.