Add widget input example

Add widget input example for the newly created Image-to-Image widget

cc:

@patrickvonplaten

README.md

@@ -6,6 +6,9 @@ tags:
 - controlnet
 - stable-diffusion
 - image-to-image
+widget:
+- src: https://huggingface.co/datasets/mishig/sample_images/resolve/main/canny-edge.jpg
+  prompt: Girl with Pearl Earring
 ---
 
 # Controlnet - *Canny Version*