fix: make sure the potentiel exist before computing it

lib/sasa/sasaRun.ml

@@ -49,6 +49,8 @@ open SimuState
 module StringMap = Map.Make(String)
 let (compute_potentiel: 'v SimuState.t -> RdbgPlugin.sl) =
   fun st ->
+  if Register.get_potential () = None then []
+  else
     [("potential", Data.F (SimuState.compute_potentiel st))]
     
 let (compute_legitimate: bool -> 'v SimuState.t -> bool) =