add cache example

PadelClubData/Data/Tournament.swift

@@ -2320,7 +2320,11 @@ defer {
     }
         
     public func onlineTeams() -> [TeamRegistration] {
-        unsortedTeams().filter({ $0.hasRegisteredOnline() })
+//        guard let teamRegistrations = tournamentStore?.teamRegistrations else { return [] }
+//        return teamRegistrations.cached(key: "online") { collection in
+//            collection.filter { $0.hasRegisteredOnline() }
+//        }
+        return unsortedTeams().filter({ $0.hasRegisteredOnline() })
     }
     
     public func paidOnlineTeams() -> [TeamRegistration] {