**Describe the bug**
Table creation with named tuples is broken

**How to reproduce**
ClickHouse server version 20.5.3.27

```
:) SELECT version();

┌─version()─┐
│ 20.5.3.27 │
└───────────┘
```
```
:) CREATE TABLE test.tuple
(
    `j` Tuple( a Int8, b String)
)
ENGINE = Memory;


Received exception from server (version 20.5.3):
Code: 62. DB::Exception: Received from localhost:9000. DB::Exception: Syntax error (data type): failed at position 9: Int8, b String). Expected one of: LIKE, GLOBAL NOT IN, AS, IS, OR, QuestionMark, BETWEEN, NOT LIKE, AND, Comma, alias, IN, Dot, NOT, Arrow, token, NOT IN, GLOBAL IN.
```
```
:) CREATE TABLE test.tuple_from_select
ENGINE = Memory AS
SELECT CAST((1, 'Test'), 'Tuple( a Int8,  b String)') AS j;


Received exception from server (version 20.5.3):
Code: 62. DB::Exception: Received from localhost:9000. DB::Exception: Syntax error (data type): failed at position 9: Int8, b String). Expected one of: LIKE, GLOBAL NOT IN, AS, IS, OR, QuestionMark, BETWEEN, NOT LIKE, AND, Comma, alias, IN, Dot, NOT, Arrow, token, NOT IN, GLOBAL IN.
```

**This works fine on 20.4.6.53:**
```
:) SELECT version();

┌─version()─┐
│ 20.4.6.53 │
└───────────┘
```
```
:) CREATE TABLE test.tuple
(
    `j` Tuple( a Int8, b String)
)
ENGINE = Memory;

Ok.
```
```
:) SHOW CREATE TABLE test.tuple

┌─statement───────────────────────────────────────────────────────────────────────┐
│ CREATE TABLE test.tuple
(
    `j` Tuple(
    a Int8, 
    b String)
)
ENGINE = Memory │
└─────────────────────────────────────────────────────────────────────────────────┘
```
```
:) CREATE TABLE test.tuple_from_select
ENGINE = Memory AS
SELECT CAST((1, 'Test'), 'Tuple( a Int8,  b String)') AS j;

Ok.
```
{
    TableProperties properties;
    TableLockHolder as_storage_lock;
    if (create.columns_list)
    {
        if (create.columns_list->columns)
        {
            bool sanity_check_compression_codecs = !create.attach && !context.getSettingsRef().allow_suspicious_codecs;
            properties.columns = getColumnsDescription(*create.columns_list->columns, context, sanity_check_compression_codecs);
        }
        if (create.columns_list->indices)
            for (const auto & index : create.columns_list->indices->children)
                properties.indices.push_back(
                    IndexDescription::getIndexFromAST(index->clone(), properties.columns, context));
        properties.constraints = getConstraintsDescription(create.columns_list->constraints);
    }
    else if (!create.as_table.empty())
    {
        String as_database_name = context.resolveDatabase(create.as_database);
        StoragePtr as_storage = DatabaseCatalog::instance().getTable({as_database_name, create.as_table}, context);
        
        as_storage_lock = as_storage->lockForShare(context.getCurrentQueryId(), context.getSettingsRef().lock_acquire_timeout);
        auto as_storage_metadata = as_storage->getInMemoryMetadataPtr();
        properties.columns = as_storage_metadata->getColumns();