```
create table test_lc(a LowCardinality(String)) Engine = MergeTree order by tuple();

insert into test_lc values ('abcd');

select * from test_lc format Parquet;

Exception on client:
Code: 50. DB::Exception: The type "LowCardinality" of a column "a" is not supported for conversion into a Parquet data format

Connecting to localhost:9000 as user default.
Connected to ClickHouse server version 20.3.12 revision 54433.
```

Shorter version of the test:
```
select toLowCardinality('abcd') format Parquet;

Exception on client:
Code: 50. DB::Exception: The type "LowCardinality" of a column "toLowCardinality('abcd')" is not supported for conversion into a Parquet data format

Connecting to localhost:9000 as user default.
Connected to ClickHouse server version 20.3.12 revision 54433.
```

<s>P.S. Insert works ok.</s>
```
# clickhouse-client --query="select 'ab' as a format Parquet" | clickhouse-client --query="insert into test_lc format Parquet"
```

UPD: not ok with `LowCardinality(Nullable(String))` (see comment). 
DataTypePtr internal_nested_type;
            if (arrow_type == arrow::Type::DECIMAL)
            {
                const auto * decimal_type = static_cast<arrow::DecimalType *>(arrow_column->type().get());
                internal_nested_type = std::make_shared<DataTypeDecimal<Decimal128>>(decimal_type->precision(),
                                                                                     decimal_type->scale());
            }
            else if (const auto * internal_type_it = std::find_if(arrow_type_to_internal_type.begin(), arrow_type_to_internal_type.end(),
                [=](auto && elem) { return elem.first == arrow_type; });
                internal_type_it != arrow_type_to_internal_type.end())
            {
                internal_nested_type = DataTypeFactory::instance().get(internal_type_it->second);
            }
            else
            {
                throw Exception{"The type \"" + arrow_column->type()->name() + "\" of an input column \"" + header_column.name
                        + "\" is not supported for conversion from a " + format_name + " data format",
                        ErrorCodes::CANNOT_CONVERT_TYPE};
            }
            const DataTypePtr internal_type = target_column_is_nullable ? makeNullable(internal_nested_type)
                                                                        : internal_nested_type;
            const std::string internal_nested_type_name = internal_nested_type->getName();
            const DataTypePtr column_nested_type = header_column.type->isNullable()
                                                   ? static_cast<const DataTypeNullable *>(header_column.type.get())->getNestedType()
                                                   : header_column.type;
            const DataTypePtr column_type = header_column.type;
            const std::string column_nested_type_name = column_nested_type->getName();
            ColumnWithTypeAndName column;
            column.name = header_column.name;
            column.type = internal_type;