8342609: jpackage test helper function incorrectly removes a directory instead of its contents only

Backport-of: 7133d1b983d7b85ba3c8dde26eb654c7ab695b07

Author: GoeLin

test/jdk/tools/jpackage/helpers/jdk/jpackage/test/TKit.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -379,7 +379,7 @@ public void accept(Path root) {
             try {
                 final List<Path> paths;
                 if (contentsOnly) {
-                    try (var pathStream = Files.walk(root, 0)) {
+                    try (var pathStream = Files.list(root)) {
                         paths = pathStream.collect(Collectors.toList());
                     }
                 } else {