feat: add reduce kernels #2704

Job	Run time
Linux-cppyy	48s
Linux-ROOT	4m 5s
Run Tests (windows-latest, 3.12, x64, full)	4m 49s
Run Tests (windows-latest, 3.11, x64, full)	4m 38s
Run Tests (windows-latest, 3.10, x64, full)	4m 15s
Run Tests (windows-latest, 3.9, x64, full)	4m 7s
Run Tests (windows-latest, 3.8, x64, full)	4m 33s
Run Tests (ubuntu-latest, 3.12, x64, full)	3m 16s
Run Tests (ubuntu-latest, 3.11, x64, full)	5m 17s
Run Tests (ubuntu-latest, 3.10, x64, full)	5m 16s
Run Tests (ubuntu-latest, 3.9, x64, full)	5m 7s
Run Tests (ubuntu-latest, 3.8, x64, full)	5m 39s
Run Tests (macos-11, 3.12, x64, full)	5m 13s
Run Tests (macos-11, 3.11, x64, full)	8m 42s
Run Tests (macos-11, 3.10, x64, full)	9m 54s
Run Tests (macos-11, 3.9, x64, full)	8m 49s
Run Tests (macos-11, 3.8, x64, full)	9m 2s
Run Tests (3.9, x86, windows-latest, full)	4m 37s
Run Tests (3.9, x86, windows-latest, numpy1)	5m 28s
Run Tests (3.8, x64, ubuntu-latest, minimal)	3m 4s
Run Tests (pypy3.9, x64, ubuntu-latest, pypy)	3m 0s
	1h 49m 39s

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