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

M(key_fixed_string) \
        M(keys128)          \
        M(keys256)          \
        M(serialized)       \
#define M(NAME) \
    if (merge_method == AggregatedDataVariants::Type::NAME) \
        merge_method = AggregatedDataVariants::Type::NAME ## _hash64; \
    APPLY_FOR_VARIANTS_THAT_MAY_USE_BETTER_HASH_FUNCTION(M)
#undef M
#undef APPLY_FOR_VARIANTS_THAT_MAY_USE_BETTER_HASH_FUNCTION
    
    AggregatedDataVariants result;
    
    result.aggregator = this;
    result.init(merge_method);
    result.keys_size = params.keys_size;
    result.key_sizes = key_sizes;
    for (Block & block : blocks)
    {
        if (isCancelled())
            return {};
        if (bucket_num >= 0 && block.info.bucket_num != bucket_num)
            bucket_num = -1;
        if (result.type == AggregatedDataVariants::Type::without_key || is_overflows)
            mergeWithoutKeyStreamsImpl(block, result);
    #define M(NAME, IS_TWO_LEVEL) \
        else if (result.type == AggregatedDataVariants::Type::NAME) \
            mergeStreamsImpl(block, result.aggregates_pool, *result.NAME, result.NAME->data, nullptr, false);
        APPLY_FOR_AGGREGATED_VARIANTS(M)
    #undef M