**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.

using Type = std::decay_t<decltype(dictionary_attribute_type)>;
            using AttributeType = typename Type::AttributeType;
            using ValueType = DictionaryValueType<AttributeType>;
            using ColumnProvider = DictionaryAttributeColumnProvider<AttributeType>;
            using ColumnType = typename ColumnProvider::ColumnType;
            const auto attribute_values_column_typed = typeid_cast<const ColumnType *>(attribute_values_column.get());
            if (!attribute_values_column_typed)
                throw Exception(ErrorCodes::BAD_ARGUMENTS, "An attribute type should be same as dictionary type");
            ColumnType & result_column_typed = static_cast<ColumnType &>(*result);
            if constexpr (std::is_same_v<ValueType, Array>)
            {
                getItemsImpl<ValueType>(
                    requested_key_points,
                    [&](size_t row) { return (*attribute_values_column)[row].get<Array>(); },
                    [&](Array & value) { result_column_typed.insert(value); },
                    default_value_provider);
            }
            else if constexpr (std::is_same_v<ValueType, StringRef>)
            {
                getItemsImpl<ValueType>(
                    requested_key_points,
                    [&](size_t row) { return attribute_values_column->getDataAt(row); },
                    [&](StringRef value) { result_column_typed.insertData(value.data, value.size); },
                    default_value_provider);
            }
            else
            {
                auto & attribute_data = attribute_values_column_typed->getData();
                auto & result_data = result_column_typed.getData();
                getItemsImpl<ValueType>(