[Single File] Add Single File support for HunYuan video

[DN6]

What does this PR do?

• Add single file support support for hunyuan.

• Change passing revision to load_config and instead use config_revision option. This is because revision is passed to both the checkpoint downloading and config downloading steps. But if you're downloading a checkpoint from one repo and loading the config from another there is a mismatch. Since we haven't shipped revision for configs yet, this is a safe change.

Fixes # (issue)

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[a-r-r-o-w]

Thanks!

Context for the suggested change: #10344