Fix link of bird

Change the address of the example bird to the current link.

README.md

@@ -98,7 +98,7 @@ import torch
 import numpy as np
 from diffusers.utils import load_image
 
-image = load_image("https://huggingface.co/lllyasviel/sd-controlnet-hed/resolve/main/images/bird.png")
+image = load_image("https://huggingface.co/lllyasviel/sd-controlnet-canny/tree/main/images/bird.png")
 image = np.array(image)
 
 low_threshold = 100