JNI support for segmented reduce

[revans2]

This adds in JNI support for #9621. It also adds in a helper API to allow us to do the processing on a list easily.

[codecov]

Codecov Report

Merging #10413 (e17f4dc) into branch-22.04 (b613394) will increase coverage by 0.02%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##           branch-22.04   #10413      +/-   ##
================================================
+ Coverage         86.13%   86.16%   +0.02%     
================================================
  Files               139      139              
  Lines             22460    22457       -3     
================================================
+ Hits              19347    19351       +4     
+ Misses             3113     3106       -7     

Impacted Files	Coverage Δ
python/cudf/cudf/core/frame.py	91.72% <0.00%> (ø)
python/cudf/cudf/core/single_column_frame.py	97.01% <0.00%> (ø)
python/cudf/cudf/core/column/string.py	88.39% <0.00%> (+0.12%)	⬆️
python/cudf/cudf/core/column/column.py	89.16% <0.00%> (+0.17%)	⬆️
python/cudf/cudf/core/tools/datetimes.py	84.49% <0.00%> (+0.30%)	⬆️
python/cudf/cudf/core/groupby/groupby.py	91.92% <0.00%> (+0.43%)	⬆️
python/cudf/cudf/core/column/lists.py	90.56% <0.00%> (+0.47%)	⬆️

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[firestarman]

LGTM

[jlowe]

@gpucibot merge