use FailThrough when available

common/addons/language-yaml/src/main/java/com/dfsek/terra/addons/yaml/YamlAddon.java

@@ -25,6 +25,7 @@ public class YamlAddon extends TerraAddon {
                 .then(event -> event.getLoader().open("", ".yml").thenEntries(entries -> entries.forEach(entry -> {
                     main.getDebugLogger().info("Discovered config " + entry.getKey());
                     event.register(entry.getKey(), new YamlConfiguration(entry.getValue(), entry.getKey()));
-                })));
+                })))
+                .failThrough();
     }
 }