Fixed TPC eta acceptance magic number

Author: lcernusa

PWGCF/TwoParticleCorrelations/Tasks/flowDecorrelation.cxx

@@ -1751,7 +1751,7 @@ struct FlowDecorrelation {
       // loop over all TPC tracks
       for (auto const& track2 : tracks2) {
 
-        if (std::abs(track2.eta()) > 0.9)
+        if (std::abs(track2.eta()) > tpcEtaAcceptance)
           continue;
 
         if (step >= CorrelationContainer::kCFStepTrackedOnlyPrim && !track2.isPhysicalPrimary())