FIX-#7383: Avoid broadcast issue in partition manager with custom `NPartitions` #16125

Job	Run time
execution-filter	8s
python-filter	1s
lint (mypy)	2m 10s
lint (flake8)	13s
Test API, headers and no-engine mode	1m 44s
test-asv-benchmarks	17s
test-clean-install-ubuntu	3m 3s
test-ubuntu (engine unidist ${{ matrix.unidist-backend }}, python ${{ matrix.python-version }})	0s
test-clean-install-windows	3m 12s
test-ubuntu (engine python, python 3.9, group_1)	20m 54s
test-windows (engine python, python 3.9, group_1)	39m 55s
Test BaseOnPython execution, Python 3.9"	16m 35s
test experimental	8m 9s
test-internals	6m 39s
test-native-dataframe-mode python ${{ matrix.python-version }})	0s
test-ubuntu-sanity (engine ray, python 3.9)	18m 2s
test-spreadsheet (engine ray, python 3.9)	1m 49s
test-ubuntu-sanity (engine dask, python 3.9)	41m 46s
test-spreadsheet (engine dask, python 3.9)	1m 48s
test-ubuntu-sanity (engine unidist, python 3.9)	15m 33s
test-windows-sanity (engine ray, python 3.9)	20m 1s
test-windows-sanity (engine dask, python 3.9)	33m 30s
test-windows-sanity (engine unidist, python 3.9)	23m 33s
merge-coverage-artifacts	2s
upload-coverage	25s
	4h 19m 29s

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