Fix the formatting for the SSH config file

README_AWS.md

@@ -27,10 +27,10 @@ In case of a cluster creation, or any other case where you don't know the machin
 to setup a private key file to allow ansible to connect to the created hosts.
 
 To do so, add the the following entry to your $HOME/.ssh/config file and make it point to the private key file which allows you to login on AWS.
-'''
+```
 Host *.compute-1.amazonaws.com
   PrivateKey $HOME/.ssh/my_private_key.pem
-'''
+```
 
 Alternatively, you can configure your ssh-agent to hold the credentials to connect to your AWS instances.