Fix formatting in railties/CHANGELOG.md

Author: byroot

railties/CHANGELOG.md

@@ -6,9 +6,11 @@
 
     The Dockerfile generated by `rails new` sets the default user and group
     by name instead of UID:GID. This can cause the following error in kubernetes:
+
     ```
     container has runAsNonRoot and image has non-numeric user (rails), cannot verify user is non-root
     ```
+
     This change sets default user and group by their numeric values.
 
     *Ivan Fedotov*