Improved codestyle (8/?)

eco-core/core-proxy/src/main/java/com/willfp/eco/core/proxy/ProxyConstants.java

@@ -1,7 +1,9 @@
 package com.willfp.eco.core.proxy;
 
+import lombok.experimental.UtilityClass;
 import org.bukkit.Bukkit;
 
+@UtilityClass
 public class ProxyConstants {
     /**
      * The NMS version that the server is running on.

eco-core/core-proxy/src/main/java/com/willfp/eco/core/proxy/proxies/OpenInventoryProxy.java

@@ -11,4 +11,4 @@ public interface OpenInventoryProxy extends AbstractProxy {
      * @return The NMS inventory container.
      */
     Object getOpenInventory(@NotNull Player player);
-}
+}