[docs] [issue37432] Fix a small param type in allocation.rst

[hai shi]

Change by hai shi <shihai1991 at 126.com>:


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keywords: +patch
pull_requests: +14246
stage:  -> patch review
pull_request: https://github.com/python/cpython/pull/14430

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue37432>
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