private void relinquishDatabaseConnectivity(DatabaseContext databaseContext) {
        // reset() will handle both session clearing and trigger a database loss callback into the CC.
        reset(databaseContext);
    }
This is called to attempt the next task against ZooKeeper we want to try.

@return true if we did or attempted any work.
clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/database/DatabaseHandler.java