Update AODProducerWorkflowSpec.cxx

(cherry picked from commit 3b0a469)

Author: njacazio

Detectors/AOD/src/AODProducerWorkflowSpec.cxx

@@ -1936,15 +1936,15 @@ void AODProducerWorkflowDPL::run(ProcessingContext& pc)
       }
       auto& colParts = mcParts[iCol];
       auto nParts = colParts.size();
-      for (const auto colPart : colParts) {
+      for (auto colPart : colParts) {
         auto eventID = colPart.entryID;
         auto sourceID = colPart.sourceID;
         // enable embedding: if several colParts exist, then they are
         // saved as one collision
         if (nParts == 1 || sourceID == 0) {
           // FIXME:
           // use generators' names for generatorIDs (?)
-          const auto& header = mcReader->getMCEventHeader(sourceID, eventID);
+          auto& header = mcReader->getMCEventHeader(sourceID, eventID);
           updateMCHeader(mcCollisionsCursor.cursor,
                          hepmcXSectionsCursor.cursor,
                          hepmcPdfInfosCursor.cursor,