Remove superfluous addToClassHierarchy call for Enum types

Closes gh-32906

Author: jhoeller

spring-core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -561,9 +561,8 @@ private List<Class<?>> getClassHierarchy(Class<?> type) {
 			}
 
 			if (Enum.class.isAssignableFrom(type)) {
-				addToClassHierarchy(hierarchy.size(), Enum.class, array, hierarchy, visited);
 				addToClassHierarchy(hierarchy.size(), Enum.class, false, hierarchy, visited);
-				addInterfacesToClassHierarchy(Enum.class, array, hierarchy, visited);
+				addInterfacesToClassHierarchy(Enum.class, false, hierarchy, visited);
 			}
 
 			addToClassHierarchy(hierarchy.size(), Object.class, array, hierarchy, visited);