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.
const MergeTreeData & storage_,
            const String & source_dir_)
            : storage(storage_)
            , source_dir(source_dir_)
        {
        }
        
        void addPart(const String & old_name, const String & new_name, const DiskPtr & disk);
        
        void tryRenameAll();
        
        ~PartsTemporaryRename();
        struct RenameInfo
        {
            String old_name;
            String new_name;
            
            DiskPtr disk;
        };
        const MergeTreeData & storage;
        const String source_dir;
        std::vector<RenameInfo> old_and_new_names;
        bool renamed = false;
    };
    
    struct MergingParams
    {
        
        enum Mode