[PWGDQ] Update HistogramsLibrary.cxx (#10925)

Co-authored-by: Debadatta3337 <debadatt.behera@cern.ch>

Author: Debadatta3337

PWGDQ/Core/HistogramsLibrary.cxx

@@ -947,6 +947,7 @@ void o2::aod::dqhistograms::DefineHistograms(HistogramManager* hm, const char* h
       if (subGroupStr.Contains("mult")) {
         hm->AddHistogram(histClass, "Mass_Pt_MultFV0A", "", false, 200, 0.0, 5.0, VarManager::kMass, 40, 0.0, 40.0, VarManager::kPt, 100, 0.0, 25000.0, VarManager::kMultFV0A);
         hm->AddHistogram(histClass, "Mass_VtxNcontribReal", "Mass vs VtxNcontribReal", false, 200, 0.0, 5.0, VarManager::kMass, 200, 0, 200.0, VarManager::kVtxNcontribReal);
+        hm->AddHistogram(histClass, "Mass_VtxNcontribReal_VtxZ", "Mass vs VtxNcontribReal vs VtxZ", false, 200, 2.0, 5.0, VarManager::kMass, 150, 0, 150.0, VarManager::kVtxNcontribReal, 20, -10.0, 10.0, VarManager::kVtxZ);
         hm->AddHistogram(histClass, "VtxZ_VtxNcontribReal", "VtxZ vs VtxNcontribReal", false, 240, -12.0, 12.0, VarManager::kVtxZ, 200, 0, 200.0, VarManager::kVtxNcontribReal);
       }
       if (subGroupStr.Contains("polarization")) {