Resolve "pi0 resolution for ECal barrel"

Closes #19 (closed)

benchmarks/barrel_ecal/scripts/emcal_barrel_pions_analysis.cxx

@@ -19,6 +19,7 @@
 #include "TH1.h"
 #include "TF1.h"
 #include "TH1D.h"
+#include <TFitResult.h>
 
 using ROOT::RDataFrame;
 using namespace ROOT::VecOps;