Added zh-CN to language manager

Author: KartoffelChipss

src/main/java/org/strassburger/serverLinksZ/util/LanguageManager.java

@@ -11,7 +11,7 @@
 
 public class LanguageManager {
     private final JavaPlugin plugin = ServerLinksZ.getInstance();
-    public static final List<String> defaultLangs = List.of("en-US", "de-DE");
+    public static final List<String> defaultLangs = List.of("en-US", "de-DE", "zh-CN");
 
     private HashMap<String, String> translationMap;
     private FileConfiguration langConfig;