Style: Manually revert changes made to UsernameAvailability enum

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/check_nick/UsernameAvailability.java

@@ -1,8 +1,10 @@
 package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.check_nick;
+
 /** Represents the availability status of a username */
-enum UsernameAvailability {
+public enum UsernameAvailability {
     /** Username is available */
     FREE,
+
     /** Username is already in use */
     TAKEN
-}
+}