[Training] remove depcreated method from lora scripts again (#6266)

* remove depcreated method from lora scripts

* check code quality

examples/text_to_image/train_text_to_image_lora_sdxl.py

@@ -22,7 +22,6 @@ import os
 import random
 import shutil
 from pathlib import Path
-from typing import Dict
 
 import datasets
 import numpy as np
@@ -436,22 +435,6 @@ DATASET_NAME_MAPPING = {
 }
 
 
-def unet_attn_processors_state_dict(unet) -> Dict[str, torch.tensor]:
-    """
-    Returns:
-        a state dict containing just the attention processor parameters.
-    """
-    attn_processors = unet.attn_processors
-
-    attn_processors_state_dict = {}
-
-    for attn_processor_key, attn_processor in attn_processors.items():
-        for parameter_key, parameter in attn_processor.state_dict().items():
-            attn_processors_state_dict[f"{attn_processor_key}.{parameter_key}"] = parameter
-
-    return attn_processors_state_dict
-
-
 def tokenize_prompt(tokenizer, prompt):
     text_inputs = tokenizer(
         prompt,