**Describe the bug**
```
SELECT number % 100 AS k, sumArray(emptyArrayUInt8()) AS v FROM numbers(10) GROUP BY k
```
Fails under ASan.

{
        LOG_TRACE(&Poco::Logger::get(__PRETTY_FUNCTION__), "Waiting for threads to finish");
        
        
        if (parallel_merge_data)
            parallel_merge_data->pool.wait();
    }
protected:
    Block readImpl() override
    {
        if (data.empty())
            return {};
        if (current_bucket_num >= NUM_BUCKETS)
            return {};
        AggregatedDataVariantsPtr & first = data[0];
        if (current_bucket_num == -1)
        {
            ++current_bucket_num;
            if (first->type == AggregatedDataVariants::Type::without_key || aggregator.params.overflow_row)
            {
                aggregator.mergeWithoutKeyDataImpl(data);
                return aggregator.prepareBlockAndFillWithoutKey(
                    *first, final, first->type != AggregatedDataVariants::Type::without_key);
            }
        }
        if (!first->isTwoLevel())
        {
            if (current_bucket_num > 0)
                return {};
            if (first->type == AggregatedDataVariants::Type::without_key)