TauTrig : fix memory leak issue in Run3 offline monitoring (ATR-25480)
This MR is going to fix a memory leak issue during Truth particle analysis in Run3 TauTrigger offline monitoring. The issue was mentioned by @vmartin in https://its.cern.ch/jira/browse/ATR-25480 and also confirmed through private local and GRID test.
IMPORTANT : this MR is a temporary fix until this part of the code will be optimised to use one smart pointers or deep-copy for safer memory allocation management