protected MongoCollection getTicketCollectionInstance(final String mapName) {
        return FunctionUtils.doUnchecked(() -> {
            val inst = mongoTemplate.getCollection(mapName);
            LOGGER.debug("Located MongoDb collection instance [{}]", mapName);
            return inst;
        });
    }
Calculate the time at which the ticket is eligible for automated deletion by MongoDb.
Makes the assumption that the CAS server date and the Mongo server date are in sync.
support/cas-server-support-mongo-ticket-registry/src/main/java/org/apereo/cas/ticket/registry/MongoDbTicketRegistry.java