**Describe the issue**
Can't insert `String` data to column with `LowCardinality` type.

Starting from 21.1 this query fails

**How to reproduce**
```sql
CREATE TABLE default.lc_test
(   
    `id` LowCardinality(String)
)
ENGINE = MergeTree
PARTITION BY tuple()
ORDER BY id;

Ok.
0 rows in set. Elapsed: 0.003 sec.


insert into lc_test values (toString('a'));
Exception on client:
Code: 49. DB::Exception: Bad cast from type DB::ColumnString to DB::ColumnLowCardinality: data for INSERT was parsed from query

```

**Additional context**
related to issue https://github.com/DarkWanderer/ClickHouse.Client/issues/66

version 20.12 ok
for (size_t i = 0; i < array_value_size; ++i)
            {
                if (array_value[i].isNull())
                    array_value[i] = element_type.getDefault();
                tryToReplaceNullFieldsInComplexTypesWithDefaultValues(array_value[i], element_type);
            }
        }
        else if (type.isMap() && value.getType() == Field::Types::Map)
        {
            const DataTypeMap & type_map = static_cast<const DataTypeMap &>(data_type);
            const auto & key_type = *type_map.getKeyType();
            const auto & value_type = *type_map.getValueType();
            auto & map = value.get<Map>();
            size_t map_size = map.size();
            for (size_t i = 0; i < map_size; ++i)
            {
                auto & map_entry = map[i].get<Tuple>();
                auto & entry_key = map_entry[0];
                auto & entry_value = map_entry[1];
                if (entry_key.isNull() && !key_type.isNullable())
                    entry_key = key_type.getDefault();
                tryToReplaceNullFieldsInComplexTypesWithDefaultValues(entry_key, key_type);
                if (entry_value.isNull() && !value_type.isNullable())
                    entry_value = value_type.getDefault();
                tryToReplaceNullFieldsInComplexTypesWithDefaultValues(entry_value, value_type);
            }
        }
    }
}
bool ValuesBlockInputFormat::parseExpression(IColumn & column, size_t column_idx)