update readme

Author: adbenitez

README.md

@@ -5,5 +5,5 @@ A [Heroku](https://heroku.com) deployment of [SimpleBot](https://github.com/simp
 
 To setup your own bot instance just click the button below:
 
-.. image:: https://www.herokucdn.com/deploy/button.svg
-   :target: https://heroku.com/deploy?template=https://github.com/adbenitez/simplebot-www-heroku/tree/main/
+[![Deploy](https://www.herokucdn.com/deploy/button.svg)](https://heroku.com/deploy?template=https://github.com/adbenitez/simplebot-www-heroku/tree/main/)
+