BUG: Fix na_position type in IndexEngine #22314

Job	Run time
Pyodide build	13m 35s
Linux-32-bit	13m 21s
Linux-Musl	13m 21s
python-freethreading	13m 34s
python-dev (macOS-14)	13m 37s
python-dev (macOS-13)	13m 39s
python-dev (ubuntu-22.04)	13m 35s
python-dev (windows-latest)	13m 28s
macos-13 actions-310.yaml	13m 39s
macos-13 actions-311.yaml	13m 39s
macos-13 actions-312.yaml	13m 40s
macos-14 actions-310.yaml	13m 41s
macos-14 actions-311.yaml	13m 42s
macos-14 actions-312.yaml	13m 40s
windows-latest actions-311.yaml	13m 32s
windows-latest actions-310.yaml	13m 30s
windows-latest actions-312.yaml	13m 34s
Minimum Versions	13m 36s
Future infer strings (without pyarrow)	18m 20s
Locale: zh_CN	13m 35s
Locale: it_IT	13m 35s
Downstream Compat	5m 54s
Numpy Dev	13m 35s
Pyarrow Nightly	13m 36s
Future infer strings	18m 20s
Pypy	1m 43s
ubuntu-22.04 actions-311.yaml	18m 19s
ubuntu-22.04 actions-310.yaml	18m 20s
ubuntu-22.04 actions-312.yaml	18m 22s
ubuntu-24.04-arm actions-311.yaml	18m 19s
ubuntu-24.04-arm actions-312.yaml	18m 20s
ubuntu-24.04-arm actions-310.yaml	18m 19s
	7h 33m 0s

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