fix(sd3): fix deletion of text_encoders etc (#8951)

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

examples/dreambooth/train_dreambooth_lora_sd3.py

@@ -1454,7 +1454,7 @@ def main(args):
             )
 
     # Clear the memory here
-    if not args.train_text_encoder and train_dataset.custom_instance_prompts:
+    if not args.train_text_encoder and not train_dataset.custom_instance_prompts:
         del tokenizers, text_encoders
         # Explicitly delete the objects as well, otherwise only the lists are deleted and the original references remain, preventing garbage collection
         del text_encoder_one, text_encoder_two, text_encoder_three