[BugFix] Fix non-tensor passage in _StepMDP #10508

Job	Run time
build-wheel-linux (3.8, cp38-cp38, --index-url https://download.pytorch.org/whl/cpu, "['cpu', '11...	1m 29s
build-wheel-windows (3.8, 3.8)	3m 19s
build-wheel-linux (3.9, cp39-cp39, --index-url https://download.pytorch.org/whl/cpu, "['cpu', '11...	1m 36s
build-wheel-windows (3.9, 3.9)	3m 18s
build-wheel-linux (3.10, cp310-cp310, --index-url https://download.pytorch.org/whl/cpu, "['cpu', ...	1m 40s
build-wheel-windows (3.10, 3.10.3)	3m 59s
build-wheel-linux (3.11, cp311-cp311, --index-url https://download.pytorch.org/whl/cpu, "['cpu', ...	1m 32s
build-wheel-windows (3.11, 3.11)	2m 20s
test-wheel (linux, ubuntu-20.04, 3.8)	2m 28s
test-wheel (linux, ubuntu-20.04, 3.9)	2m 21s
test-wheel (linux, ubuntu-20.04, 3.10)	2m 15s
test-wheel (linux, ubuntu-20.04, 3.11)	2m 12s
test-wheel-windows (3.8)	3m 39s
test-wheel-windows (3.9)	4m 49s
test-wheel-windows (3.10)	3m 57s
test-wheel-windows (3.11)	4m 43s
	45m 37s

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