Fix test image link. (#1193)

Author: nikoshell

public/53140703878_8d29805478_h.jpg

@@ -249,7 +249,7 @@ Barking up the right tree
 ## Caption
 
 <Image
-  src="https://live.staticflickr.com/65535/53140703878_8d29805478_h.jpg"
+  src="/53140703878_8d29805478_h.jpg"
   alt="lalo, remote image"
   width="400"
   height="400"