**How to reproduce**
Clickhouse server 20.13.1.5273
```
CREATE TABLE default.test
(
`key` UInt32,
`ts` DateTime CODEC(DoubleDelta, LZ4),
`db_time` DateTime DEFAULT now() COMMENT 'spout-ignore' CODEC(DoubleDelta, LZ4)
)
ENGINE = MergeTree
PARTITION BY toStartOfTenMinutes(db_time)
ORDER BY (key, ts)
TTL db_time + toIntervalHour(3)
SETTINGS index_granularity = 8192, merge_with_ttl_timeout = 3600, min_rows_for_compact_part = 1000000, min_bytes_for_compact_part = 200000000, in_memory_parts_enable_wal = 0;


INSERT INTO test(key, ts) SELECT number % 1000, now() + intDiv(number,1000) FROM numbers(500);

SELECT * FROM test;
500 rows in set. Elapsed: 0.003 sec.

DETACH TABLE test;

ATTACH TABLE test;

SELECT * FROM test;

0 rows in set. Elapsed: 0.002 sec.
```

**Expected behavior**
Clickhouse would flush parts on disk.
calculated_checksums.checkEqual(part->checksums, true);
                auto out = disk->writeFile(tmp_checksums_path, 4096);
                part->checksums.write(*out);
                disk->moveFile(tmp_checksums_path, checksums_path);
                results.emplace_back(part->name, true, "Checksums recounted and written to disk.");
            }
            catch (const Exception & ex)
            {
                if (disk->exists(tmp_checksums_path))
                    disk->removeFile(tmp_checksums_path);
                results.emplace_back(part->name, false,
                    "Check of part finished with error: '" + ex.message() + "'");
            }
        }
        else
        {
            try
            {
                checkDataPart(part, true);
                results.emplace_back(part->name, true, "");
            }
            catch (const Exception & ex)
            {
                results.emplace_back(part->name, false, ex.message());
            }
        }
    }
    return results;
}
RestoreDataTasks StorageMergeTree::restoreFromBackup(const BackupPtr & backup, const String & data_path_in_backup, const ASTs & partitions, ContextMutablePtr local_context)