Correct `sample_size` of Stable Diffusion 2's unet to have correct width and height default

Since `diffusers==0.9.0` the width and height is automatically inferred from the `sample_size` attribute of your unet's config. It seems like your diffusion model has the same architecture as Stable Diffusion 2 which means that when using this model, by default an image size of 768x768 should be generated. This in turn means the unet's sample size should be 96.

In order to suppress to update your configuration on the fly and to suppress the deprecation warning added in this PR: https://github.com/huggingface/diffusers/pull/1406/files#r1035703505 it is strongly recommended to merge this PR.

unet/config.json

@@ -33,7 +33,7 @@
   "norm_eps": 1e-05,
   "norm_num_groups": 32,
   "out_channels": 4,
-  "sample_size": 34,
+  "sample_size": 96,
   "up_block_types": [
     "UpBlock2D",
     "CrossAttnUpBlock2D",