[refactor] remove conv_cache from CogVideoX VAE (#9524)

* remove conv cache from the layer and pass as arg instead

* make style

* yiyi's cleaner implementation

Co-Authored-By: YiYi Xu <yixu310@gmail.com>

* sayak's compiled implementation

Co-Authored-By: Sayak Paul <spsayakpaul@gmail.com>

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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
Co-authored-by: YiYi Xu <yixu310@gmail.com>

Author: 3 people