chore: readme typo

Author: alphastrata

README.md

@@ -178,7 +178,7 @@ See the [guide](./CONTRIBUTING.md)
   </tr>
   <tr>
     <td><img src="readme_assets/shadertoy-default-gif-example.gif" alt="screenshot" width="50%"></td>
-    <td><img src="readme_assets/zippy-zap-example.gif.gif" alt="screenshot" width="50%"></td>
+    <td><img src="readme_assets/zippy-zap-example.gif" alt="screenshot" width="50%"></td>
   </tr>
 </table>