**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.
if (!buf->eof())
            throw Exception("Bad version file: " + fullPath(version_file.second, version_file.first), ErrorCodes::CORRUPTED_DATA);
    }
    if (format_version < min_format_version)
    {
        if (min_format_version == MERGE_TREE_DATA_MIN_FORMAT_VERSION_WITH_CUSTOM_PARTITIONING.toUnderType())
            throw Exception(
                "MergeTree data format version on disk doesn't support custom partitioning",
                ErrorCodes::METADATA_MISMATCH);
    }
    String reason;
    if (!canUsePolymorphicParts(*settings, &reason) && !reason.empty())
        LOG_WARNING(log, "{} Settings 'min_rows_for_wide_part', 'min_bytes_for_wide_part', "
            "'min_rows_for_compact_part' and 'min_bytes_for_compact_part' will be ignored.", reason);
    common_assignee_trigger = [this] (bool delay) noexcept
    {
        if (delay)
            background_operations_assignee.postpone();
        else
            background_operations_assignee.trigger();
    };
    moves_assignee_trigger = [this] (bool delay) noexcept
    {
        if (delay)
            background_moves_assignee.postpone();
        else
            background_moves_assignee.trigger();
    };
}
StoragePolicyPtr MergeTreeData::getStoragePolicy() const