Implement detector benchmark for the barrel calorimeter for energy resolution

benchmarks/barrel_ecal/scripts/emcal_barrel_energy_scan_analysis.cxx

@@ -191,8 +191,8 @@ void emcal_barrel_electrons_energy_scan_analysis()
     TGraph gr_fsam_res(scanned_energies.size());
     for (const auto& E : scanned_energies) {
         auto [fsam, fsam_res] = extract_sampling_fraction_parameters(E);
-        gr_fsam.AddPoint(gr_fsam.GetN(),E,fsam);
-        gr_fsam_res.AddPoint(gr_fsam_res.GetN(),E,fsam_res);
+        gr_fsam.SetPoint(gr_fsam.GetN(),E,fsam);
+        gr_fsam_res.SetPoint(gr_fsam_res.GetN(),E,fsam_res);
     }
     TCanvas* c5 = new TCanvas("c5", "c5", 700, 500);
     c5->cd();