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.
{
    
    Int64 sources_data_version = result_part->parts.at(0)->info.getDataVersion();
    Int64 result_data_version = result_part->part_info.getDataVersion();
    if (sources_data_version != result_data_version)