Improve speed of lexicographical_partition_ranges

[alamb]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

There are certain operations related to sorting (like implementing window functions) that benefit from determining where a set of rows differs in equality.

That is what https://docs.rs/arrow/latest/arrow/compute/fn.lexicographical_partition_ranges.html does

Describe the solution you'd like
I would like https://docs.rs/arrow/latest/arrow/compute/fn.lexicographical_partition_ranges.html to go as fast as possible

Describe alternatives you've considered

Additional context