[PWGDQ] Adding check if MC particle exists in mftMchMatcher (#15456)

Co-authored-by: Maurice Coquet <mcoquet@alicecerno2.cern.ch>

Author: mcoquet642

PWGDQ/Tasks/mftMchMatcher.cxx

@@ -544,6 +544,10 @@ struct mftMchMatcher {
     auto const& mchTrack = muonTrack.template matchMCHTrack_as<TMUONS>();
     auto const& mftTrack = muonTrack.template matchMFTTrack_as<TMFTS>();
 
+    if (!muonTrack.has_mcParticle() || !mftTrack.has_mcParticle()) {
+      return result;
+    }
+
     bool isPaired = isPairedMuon(mchTrack.globalIndex(), matchablePairs);
     std::pair<int64_t, int64_t> matchPair{mchTrack.globalIndex(), mftTrack.globalIndex()};
     bool isTrueMatch = std::find(matchablePairs.begin(), matchablePairs.end(), matchPair) != matchablePairs.end();