[PWGLF,PWGMM] Add generator-level vs reco-level flattenicity task (#17353)

Co-authored-by: PaolaVT <paovargas@MacBook-Air-de-Paola.local>

Author: PaolaVT

PWGMM/UE/Tasks/CMakeLists.txt

@@ -22,4 +22,9 @@ o2physics_add_dpl_workflow(ue-zdc-analysis
 o2physics_add_dpl_workflow(dedx-analysis
                     SOURCES dedxAnalysis.cxx
                     PUBLIC_LINK_LIBRARIES O2::Framework O2Physics::AnalysisCore
-                    COMPONENT_NAME Analysis)
+                    COMPONENT_NAME Analysis)
+
+o2physics_add_dpl_workflow(flattenicity-task
+                    SOURCES flattenicityTask.cxx
+                    PUBLIC_LINK_LIBRARIES O2::Framework O2Physics::AnalysisCore
+                    COMPONENT_NAME Analysis)