allow explicit tokenizer & text_encoder in unload_textual_inversion (#6977)
* allow passing tokenizer & text_encoder to unload_textual_inversion
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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
Co-authored-by: YiYi Xu <yixu310@gmail.com>
Co-authored-by: Fabio Rigano <fabio2rigano@gmail.com>
Co-authored-by: Linoy Tsaban <57615435+linoytsaban@users.noreply.github.com>