For some reasons when we delete a MergeTree Part in atomic way something may go wrong - and leave the `delete_tmp_*` folder or it's part on disk. This may lead to a disk space consumption over time.

It's suggested to delete this folders at least at server start-up. Current solution with `clearOldTemporaryDirectories()` doesn't work because this method is called periodically from a thread without any locks or advisory on folders - it may cause the race conditions.
zkutil::Strings replicas;
    zkutil::Strings active_replicas;
    String best_replica;
    {
        
        replicas = zookeeper->getChildren(fs::path(from) / "replicas");
        
        active_replicas.reserve(replicas.size());
        for (const String & replica : replicas)
            if (zookeeper->exists(fs::path(from) / "replicas" / replica / "is_active"))
                active_replicas.push_back(replica);
        if (active_replicas.empty())
            throw Exception("No active replicas for shard " + from, ErrorCodes::NO_ACTIVE_REPLICAS);
        /** You must select the best (most relevant) replica.
        * This is a replica with the maximum `log_pointer`, then with the minimum `queue` size.
        * NOTE This is not exactly the best criteria. It does not make sense to download old partitions,
        *  and it would be nice to be able to choose the replica closest by network.
        * NOTE Of course, there are data races here. You can solve it by retrying.
        */
        Int64 max_log_pointer = -1;
        UInt64 min_queue_size = std::numeric_limits<UInt64>::max();
        for (const String & replica : active_replicas)
        {
            String current_replica_path = fs::path(from) / "replicas" / replica;
            String log_pointer_str = zookeeper->get(fs::path(current_replica_path) / "log_pointer");
            Int64 log_pointer = log_pointer_str.empty() ? 0 : parse<UInt64>(log_pointer_str);
            Coordination::Stat stat;
            zookeeper->get(fs::path(current_replica_path) / "queue", &stat);
            size_t queue_size = stat.numChildren;
            if (log_pointer > max_log_pointer