use existing api

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/PackageJsonGenerator.java

@@ -21,7 +21,6 @@
 import software.amazon.smithy.codegen.core.SymbolDependency;
 import software.amazon.smithy.model.node.Node;
 import software.amazon.smithy.model.node.ObjectNode;
-import software.amazon.smithy.typescript.codegen.util.MergeJsonNodes;
 import software.amazon.smithy.utils.IoUtils;
 import software.amazon.smithy.utils.SmithyInternalApi;
 
@@ -44,11 +43,19 @@ static void writePackageJson(
     ) {
         // Write the package.json file.
         InputStream resource = PackageJsonGenerator.class.getResourceAsStream("base-package.json");
-        ObjectNode node = MergeJsonNodes.mergeWithScripts(
-            Node.parse(IoUtils.toUtf8String(resource))
-                .expectObjectNode(),
-            settings.getPackageJson()
-        );
+
+        ObjectNode userSuppliedPackageJson = settings.getPackageJson();
+        ObjectNode defaultPackageJson = Node.parse(IoUtils.toUtf8String(resource))
+            .expectObjectNode();
+
+        ObjectNode mergedScripts = defaultPackageJson.expectObjectNode("scripts")
+            .merge(
+                userSuppliedPackageJson.getObjectMember("scripts")
+                    .orElse(ObjectNode.builder().build())
+            );
+
+        ObjectNode node = defaultPackageJson.merge(userSuppliedPackageJson)
+            .withMember("scripts", mergedScripts);
 
         // Merge TypeScript dependencies into the package.json file.
         for (Map.Entry<String, Map<String, SymbolDependency>> depEntry : dependencies.entrySet()) {