fix import error caused due to unet refactor in huggingface#6630

Author: a-r-r-o-w

src/diffusers/pipelines/animatediff/pipeline_animatediff_video2video.py

@@ -22,7 +22,7 @@
 from ...loaders import IPAdapterMixin, LoraLoaderMixin, TextualInversionLoaderMixin
 from ...models import AutoencoderKL, ImageProjection, UNet2DConditionModel, UNetMotionModel
 from ...models.lora import adjust_lora_scale_text_encoder
-from ...models.unet_motion_model import MotionAdapter
+from ...models.unets.unet_motion_model import MotionAdapter
 from ...schedulers import (
     DDIMScheduler,
     DPMSolverMultistepScheduler,