Update co-teaching.md (formatting)

content/co-teaching.md

@@ -32,7 +32,7 @@ Advantages
 * If you need to teach anyway, combined efforts take up less time.
 * More engaging to the audience, taking some of the (sometimes daunting) expectation to "speak up" off of the students.
 * Easier on-boarding of new instructors -- one of them can be learning at the same time, either subtleties of the material or the teaching itself.
-  [Swiss-cheese](https://en.wikipedia.org/wiki/Swiss_cheese_model) principle: two "imperfect" teachers are __much__ easier to find and complement each other than the extensively-prepared, absolute expert.
+* [Swiss-cheese](https://en.wikipedia.org/wiki/Swiss_cheese_model) principle: two "imperfect" teachers are __much__ easier to find and complement each other than the extensively-prepared, absolute expert.
 
 Challenges
 ----------