```
SELECT
    CAST(([2, 1, 1023], ['', '']), 'Map(UInt8, String)') AS map,
    map[10]
```

Triggers `Assertion 'n < size()' failed` in `DB::ColumnString::operator[](unsigned long)`
https://clickhouse-test-reports.s3.yandex.net/18481/64c4ade5b0e0c9a13d6c2475431daf431fc97554/fuzzer/fuzzer.log

Introduced here: #17829
First found here: #18481
{
        const IColumn & col_from = *arguments[0].column;
        size_t size = col_from.size();
        const IDataType & data_type_to = *result_type;
        if (const ColumnString * col_from_string = checkAndGetColumn<ColumnString>(&col_from))
        {
            auto res = data_type_to.createColumn();
            IColumn & column_to = *res;
            column_to.reserve(size);
            const ColumnString::Chars & chars = col_from_string->getChars();
            const IColumn::Offsets & offsets = col_from_string->getOffsets();
            size_t current_offset = 0;