[SD3 LoRA] Fix list index out of range (#8584)
* fix
* add check
* key present is checked before
* test case draft
* aply suggestions
* changed testing repo, back to old class
* forgot docstring
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Co-authored-by: YiYi Xu <yixu310@gmail.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
