**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.
throw Exception{"Setting '" + setting_name + "' is readonly for storage '" + getName() + "'",
                                ErrorCodes::READONLY_SETTING};
            }
            if (MergeTreeSettings::isPartFormatSetting(setting_name) && !new_value)
            {
                
                auto copy = getDefaultSettings();
                copy->applyChanges(new_changes);
                String reason;
                if (!canUsePolymorphicParts(*copy, &reason) && !reason.empty())
                    throw Exception("Can't change settings. Reason: " + reason, ErrorCodes::NOT_IMPLEMENTED);
            }
        }
    }
    for (const auto & part : getDataPartsVector())
    {
        bool at_least_one_column_rest = false;
        for (const auto & column : part->getColumns())
        {
            if (!dropped_columns.count(column.name))
            {
                at_least_one_column_rest = true;
                break;
            }
        }
        if (!at_least_one_column_rest)
        {
            std::string postfix;
            if (dropped_columns.size() > 1)
                postfix = "s";