KIE Server does not delete tasks of aborted processes

KIE Server does not delete tasks that belong to a process which is aborted. All such tasks just change their state to Exited and are still visible. It can be easily fixed by registering TaskCleanUpProcessEventListener but Bussiness Central does that by default and it should also be done by default in KIE Server in order not to have different behavior on these execution servers. The uniform behavior is especially needed if we want to support both servers running on the same database.