Fix linter.

Author: mfaggin

PWGHF/TableProducer/candidateCreatorSigmac0plusplus.cxx

@@ -176,7 +176,7 @@ struct HfCandidateCreatorSigmac0plusplus {
       LOG(info) << "### ITS hitmap for soft pion";
       LOG(info) << "    >>> setSoftPiItsHitMap.size(): " << setSoftPiItsHitMap.size();
       LOG(info) << "    >>> Custom ITS hitmap dfchecked: ";
-      for (const auto it : setSoftPiItsHitMap) {
+      for (const auto& it : setSoftPiItsHitMap) {
         LOG(info) << "        Layer " << static_cast<int>(it) << " ";
       }
       LOG(info) << "############";