create a script to train autoencoderkl (#10605)
* create a script to train vae
* update main.py
* update train_autoencoderkl.py
* update train_autoencoderkl.py
* add a check of --pretrained_model_name_or_path and --model_config_name_or_path
* remove the comment, remove diffusers in requiremnets.txt, add validation_image ote
* update autoencoderkl.py
* quality
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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
