Draft: [trigEGam] Integration beteween mongroups and TrigEgammaMonitoring

This MR is to include mongroups inside the TrigEgammaMonitoring framework.

• A method was implemented in the TrigEgammaMonitCategoryMT reading, for now, the mongoups from JSON local file produced by a ART test.
• At this moment, only the primary chains was configured, and then, called inside the TrigEgammaMonitorConfigMT.py file .
• In a next MR, we will include a logic to route chains to shifter and expert folders automatically, according to their respective mongroups.

JIRA Ticket: ATR-25841 .

ping: @safarzad , @cjmeyer , @fernando , @kyjones and @jlieberm

Database/AthenaPOOL/EventSelectorAthenaPool/src/EventSelectorAthenaPool.cxx

@@ -841,6 +841,7 @@ StatusCode EventSelectorAthenaPool::seek(Context& /*ctxt*/, int evtNum) const {
          // Create DataHeader iterators
          m_headerIterator = &m_poolCollectionConverter->executeQuery();
          EventContextAthenaPool* beginIter = new EventContextAthenaPool(this);
+         m_evtCount = m_firstEvt[m_curCollection];
          next(*beginIter).ignore();
          ATH_MSG_DEBUG("Token " << m_headerIterator->eventRef().toString());
       } catch (std::exception &e) {