Replace GroupIdBlock with int[]

[dain]

Group id block was used to carry the max group id to the grouped accumulator, but the max group id is now set directly with the setGroupCount method.
An int[] is used because the GroupByHash implementations only create int group ids.

Release notes

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[lukasz-stec]

Nice! This should bring some perf improvement, I have seen 20% perf drop in some queries because of group id code was not compiled optimally by jit. using int[] will likely help with that.

[lukasz-stec]

Would it be beneficial to handle this case better?
We could still have GroupIdBLock that has two states, int[] and single value and count similar to SelectedPositions and then do

if (groupIdsBlock.isArray()) {
  // handle array
} else {
  // handle rle
}
``` in the `Accumulator`

[dain]

Maybe. I'm not sure the complexity will result in better performance in the 99% case where we don't have RLEs. My thought is we switch to int[] and establish a new base line. Then in follow up work we can investigate if adding wrapper with RLE support helps.

[lukasz-stec]

Does it make sense to also make io.trino.spi.function.GroupedAccumulatorState#setGroupId accept int instead of long?

[dain]

Yes! That will be in some follow up work.