fix(graph): fix CheckPointSerializer write read BUG (alibaba#2403)

Author: skippy-404

spring-ai-alibaba-graph-core/src/main/java/com/alibaba/cloud/ai/graph/serializer/check_point/CheckPointSerializer.java

@@ -45,8 +45,8 @@ public void write(Checkpoint object, ObjectOutput out) throws IOException {
 	public Checkpoint read(ObjectInput in) throws IOException, ClassNotFoundException {
 		return Checkpoint.builder()
 			.id(in.readUTF())
-			.nextNodeId(readNullableUTF(in).orElse(null))
 			.nodeId(readNullableUTF(in).orElse(null))
+			.nextNodeId(readNullableUTF(in).orElse(null))
 			.state((OverAllState) stateSerializer.read(in))
 			.build();
 	}