**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.
MultiVersionStorageMetadataPtr metadata;
protected:
    RWLockImpl::LockHolder tryLockTimed(
        const RWLock & rwlock, RWLockImpl::Type type, const String & query_id, const std::chrono::milliseconds & acquire_timeout) const;
public:
    
    
    
    
    TableLockHolder lockForShare(const String & query_id, const std::chrono::milliseconds & acquire_timeout);
    
    
    using AlterLockHolder = std::unique_lock<std::timed_mutex>;
    AlterLockHolder lockForAlter(const std::chrono::milliseconds & acquire_timeout);
    
    
    
    
    
    
    
    TableExclusiveLockHolder lockExclusively(const String & query_id, const std::chrono::milliseconds & acquire_timeout);
    /** Returns stage to which query is going to be processed in read() function.
      * (Normally, the function only reads the columns from the list, but in other cases,
      *  for example, the request can be partially processed on a remote server, or an aggregate projection.)
      *
      * SelectQueryInfo is required since the stage can depends on the query
      * (see Distributed() engine and optimize_skip_unused_shards,
      *  see also MergeTree engine and allow_experimental_projection_optimization).
      * And to store optimized cluster (after optimize_skip_unused_shards).