Fix markdown formatting for postgres troubleshooting MAC_SETUP.md

doc/MAC_SETUP.md

@@ -20,12 +20,15 @@ If you have an older version of postgres, `brew postgresql-upgrade-database`
 
 For a more GUI focused postgres experience, try [Postgres.app](https://postgresapp.com/) an alternative to the CLI focused default postgres
 
-If you are having trouble connecting to your local postgres database using pgAdmin or another local tool, try the following configuration:
+If you are having trouble connecting to your local postgres database using pgAdmin or another local tool, try the following configuration:  
+
+```
 Host Name: localhost
 Port: 5432
 Maintenance Database: postgres
 Username: you_mac_login_username (Can be found by calling whoami in a terminal)
 Password: password
+```
 
 ## Ruby