**Describe the unexpected behaviour**
ClickHouse returns exception if you would try to read polygon dictionary via SELECT query.

**How to reproduce**
ClickHouse version 21.10


```
CREATE DICTIONARY polygon_dict (
    key Array(Array(Array(Array(Float64)))),
    name String,
    value UInt64
)
PRIMARY KEY key
LAYOUT(POLYGON())
SOURCE(CLICKHOUSE(table 'polygon_dict_src'))
LIFETIME(MIN 300 MAX 360);

CREATE TABLE polygon_dict_src
(
    `key` Array(Array(Array(Array(Float64)))),
    `name` String,
    `value` UInt64
)
ENGINE = Log
	
INSERT INTO polygon_dict_src SELECT [[[[1.1,2.1],[5,3],[6,4],[1,4]]]], 'some', 10;


CREATE DICTIONARY polygon_dict (
    key Array(Array(Array(Array(Float64)))),
    name String,
    value UInt64
)
PRIMARY KEY key
LAYOUT(POLYGON())
SOURCE(CLICKHOUSE(table 'polygon_dict_src'))
LIFETIME(MIN 300 MAX 360);

SELECT dictGet(polygon_dict, 'name', (2., 3.)) AS x

┌─x────┐
│ some │
└──────┘

SELECT *
FROM polygon_dict

0 rows in set. Elapsed: 0.008 sec.

Received exception from server (version 21.10.1):
Code: 1. DB::Exception: Received from localhost:9000. DB::Exception: Reading the dictionary is not allowed. (UNSUPPORTED_METHOD)
```


**Expected behavior**
It's allowed to read POLYGON dictionaries via SELECT query.

else
        {
            Field default_value = default_value_extractor.getDefaultValue(requested_key_index);
            if constexpr (std::is_same_v<AttributeType, Field>)
            {
                set_value(default_value);
            }
            else if constexpr (std::is_same_v<AttributeType, Array>)
            {
                set_value(default_value.get<Array>());
            }
            else if constexpr (std::is_same_v<AttributeType, StringRef>)
            {
                auto default_value_string = default_value.get<String>();
                set_value(default_value_string);
            }
            else
            {
                set_value(default_value.get<NearestFieldType<AttributeType>>());
            }
        }
    }
    query_count.fetch_add(requested_key_points.size(), std::memory_order_relaxed);
    found_count.fetch_add(keys_found, std::memory_order_relaxed);
}
namespace
{
struct Offset
{
    Offset() = default;