Update for leanpub preview

manuscript/recipes/instapy.md

@@ -72,6 +72,7 @@ services:
 Create a variation of https://github.com/timgrossmann/InstaPy/blob/master/docker_quickstart.py at /var/data/instapy/instapy.py (the file we bind-mounted in the swarm config above)
 
 Change at least the following:
+
 ```
 insta_username = ''
 insta_password = ''