chore: fix extra colon for xml serializer (#2330)

Author: AllanZhengYP

Diff for: codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/XmlShapeSerVisitor.java

@@ -169,7 +169,7 @@ protected void serializeMap(GenerationContext context, MapShape shape) {
                         AwsProtocolUtils.writeXmlNamespace(context, valueMember, "workingNode");
                         writer.write("return acc.addChildNode(workingNode);");
                     });
-                    writer.write(", new __XmlNode($S));", valueName);
+                    writer.write(", new __XmlNode($S))", valueName);
                 });
             } else {
                 // Add @xmlNamespace value of the target member.