Update example.md

Author: britzl

sprite/tint/example.md

@@ -4,7 +4,7 @@ title: Sprite tint
 brief: This example shows how tint a sprite at run-time
 author: Defold Foundation
 scripts: tint.script
-thumbnail: bunntint_thumb.png
+thumbnail: tint_thumb.png
 ---
 
 The example uses a script to tint (color) sprites in a couple of different ways. The tint is a fragment constant on the sprite material and it is used in the sprite.fp fragment shader program to modify the color sampled from the texture.