Pythia8_i add back the by mistake reverted changes

this MR brings back the changes from !68205 (merged) which were removed later by mistake

Generators/Pythia8_i/src/Pythia8_i.cxx

@@ -78,14 +78,6 @@ Pythia8_i::Pythia8_i(const std::string &name, ISvcLocator *pSvcLocator)
   m_particleIDs["ANTIMUON"]    = ANTIMUON;
   m_particleIDs["LEAD"]        = LEAD;
 
-  ATH_MSG_INFO("XML Path is " + xmlpath());
-  m_pythia = std::make_unique<Pythia8::Pythia> (xmlpath());
-#ifdef HEPMC3
-  m_runinfo = std::make_shared<HepMC3::GenRunInfo>();
-  /// Here one can fill extra information, e.g. the used tools in a format generator name, version string, comment.
-  struct HepMC3::GenRunInfo::ToolInfo generator={std::string("Pythia8"),py8version(),std::string("Used generator")};
-  m_runinfo->tools().push_back(generator);
-#endif
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -105,6 +97,15 @@ StatusCode Pythia8_i::genInitialize() {
 
   ATH_MSG_DEBUG("Pythia8_i from genInitialize()");
 
+  ATH_MSG_INFO("XML Path is " + xmlpath());
+  m_pythia = std::make_unique<Pythia8::Pythia> (xmlpath());
+#ifdef HEPMC3
+  m_runinfo = std::make_shared<HepMC3::GenRunInfo>();
+  /// Here one can fill extra information, e.g. the used tools in a format generator name, version string, comment.
+  struct HepMC3::GenRunInfo::ToolInfo generator={std::string("Pythia8"),py8version(),std::string("Used generator")};
+  m_runinfo->tools().push_back(generator);   
+#endif
+
   bool canInit = true;
 
   m_version = m_pythia->settings.parm("Pythia:versionNumber");