Fix: Correct tensor shape comment in Mamba modeling (#37801)
* Fix: Correct tensor shape comment in Mamba modeling
* Update src/transformers/models/mamba/modeling_mamba.py
* Update src/transformers/models/mamba/modeling_mamba.py
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Co-authored-by: ShadyPi <11342288+shadypi@user.noreply.gitee.com>
Co-authored-by: Matt <Rocketknight1@users.noreply.github.com>