use memory_efficient_attention by default (#1354)
use memory_efficient_attention by default (#1354)

* use memory_efficient_attention by default

* Update src/diffusers/models/attention.py

Co-authored-by: Pedro Cuenca <4410d99cefe57ec2c2cdbd3f1d5cf862bb4fb6f8@huggingface.co>
huggingface/diffusers