Fix NPE copying forge caps

arclight-common/src/main/java/io/izzel/arclight/common/mixin/bukkit/CraftMetaItemMixin.java

@@ -145,9 +145,11 @@ public class CraftMetaItemMixin implements ItemMetaBridge {
 
     @Inject(method = "<init>*", at = @At("RETURN"))
     private void arclight$copyForgeCaps(CraftMetaItem meta, CallbackInfo ci) {
+        if (meta != null) {
             CompoundNBT forgeCaps = ((ItemMetaBridge) meta).bridge$getForgeCaps();
             if (forgeCaps != null) {
                 this.forgeCaps = forgeCaps.copy();
             }
         }
     }
+}