default int cleanTicket(final Ticket ticket) {
        return 0;
    }
Cleans up after an already-expired ticket, by running the necessary processes
such as logout notifications and more.

@param ticket the ticket
@return the number of tickets that were cleaned up during the process.
api/cas-server-core-api-ticket/src/main/java/org/apereo/cas/ticket/registry/TicketRegistryCleaner.java