Update scheduler/scheduler_config.json

Euler (Diffusers v0.25) has ZSNR support and works better than DDIM

v1: from ptx0/coco-xltest, 36000 + 21800 + 14200 steps of mixed LAION/MJ dataset and offset noise with input perturbation on a probability of 25%, 10% caption dropout, cosine LR 4e-7 to 8e-7 every 3200 steps