Update challenge count from 58 to 60

Author: commjoen

README.md

@@ -16,7 +16,7 @@
 
 Welcome to the OWASP WrongSecrets game! The game is packed with real life examples of how to _not_ store secrets in your software. Each of these examples is captured in a challenge, which you need to solve using various tools and techniques. Solving these challenges will help you recognize common mistakes & can help you to reflect on your own secrets management strategy.
 
-Can you solve all the 58 challenges?
+Can you solve all the 60 challenges?
 
 Try some of them on [our Heroku demo environment](https://wrongsecrets.herokuapp.com/).