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.
std::lock_guard lock(mutation_wait_mutex);
        mutation_wait_event.notify_all();
    }
    if (merge_entry)
    {
        auto task = std::make_shared<MergePlainMergeTreeTask>(*this, metadata_snapshot, false, Names{}, merge_entry, share_lock, common_assignee_trigger);
        task->setCurrentTransaction(std::move(transaction_for_merge), std::move(txn));
        bool scheduled = assignee.scheduleMergeMutateTask(task);
        
        
        if (!scheduled && isTTLMergeType(merge_entry->future_part->merge_type))
            getContext()->getMergeList().cancelMergeWithTTL();
        return scheduled;
    }
    if (mutate_entry)
    {
        auto task = std::make_shared<MutatePlainMergeTreeTask>(*this, metadata_snapshot, mutate_entry, share_lock, common_assignee_trigger);
        assignee.scheduleMergeMutateTask(task);
        return true;
    }
    if (has_mutations)
    {
        
        
        std::lock_guard lock(mutation_wait_mutex);
        mutation_wait_event.notify_all();
    }
    bool scheduled = false;
    if (auto lock = time_after_previous_cleanup_temporary_directories.compareAndRestartDeferred(