Remove spurious arg in training scripts (#1644)

Remove spurious arg in training scripts.

Author: pcuenca

examples/dreambooth/train_dreambooth.py

@@ -491,7 +491,7 @@ def main(args):
 
     if is_xformers_available():
         try:
-            unet.enable_xformers_memory_efficient_attention(True)
+            unet.enable_xformers_memory_efficient_attention()
         except Exception as e:
             logger.warning(
                 "Could not enable memory efficient attention. Make sure xformers is installed"

examples/text_to_image/train_text_to_image.py

@@ -367,7 +367,7 @@ def main():
 
     if is_xformers_available():
         try:
-            unet.enable_xformers_memory_efficient_attention(True)
+            unet.enable_xformers_memory_efficient_attention()
         except Exception as e:
             logger.warning(
                 "Could not enable memory efficient attention. Make sure xformers is installed"

examples/textual_inversion/textual_inversion.py

@@ -442,7 +442,7 @@ def main():
 
     if is_xformers_available():
         try:
-            unet.enable_xformers_memory_efficient_attention(True)
+            unet.enable_xformers_memory_efficient_attention()
         except Exception as e:
             logger.warning(
                 "Could not enable memory efficient attention. Make sure xformers is installed"