fix: failing test

Author: sonus21

rqueue-core/src/test/java/com/github/sonus21/rqueue/core/support/RqueueMessageUtilsTest.java

@@ -136,8 +136,8 @@ void buildMessageWithDelay() {
 
   @Test
   void buildMessageNull() {
+    // id is null so the type parameter T cannot be resolved, making conversion fail
     GenericClass<String> genericClass = new GenericClass<>();
-    genericClass.id = UUID.randomUUID().toString();
     try {
       RqueueMessageUtils.buildMessage(
           messageConverter,
@@ -155,8 +155,8 @@ void buildMessageNull() {
 
   @Test
   void buildPeriodicMessageNull() {
+    // id is null so the type parameter T cannot be resolved, making conversion fail
     GenericClass<String> genericClass = new GenericClass<>();
-    genericClass.id = UUID.randomUUID().toString();
     try {
       RqueueMessageUtils.buildPeriodicMessage(
           messageConverter,
@@ -174,8 +174,9 @@ void buildPeriodicMessageNull() {
 
   @Test
   void buildMessageReturnInvalidType() {
+    // id is null so GenericMessageConverter returns null; falls through to NoMessageConverter
+    // which wraps the object in a GenericMessage with a non-String/non-byte[] payload
     GenericClass<String> genericClass = new GenericClass<>();
-    genericClass.id = UUID.randomUUID().toString();
     try {
       RqueueMessageUtils.buildMessage(
           messageConverter2,
@@ -193,8 +194,9 @@ void buildMessageReturnInvalidType() {
 
   @Test
   void buildPeriodicMessageReturnInvalidType() {
+    // id is null so GenericMessageConverter returns null; falls through to NoMessageConverter
+    // which wraps the object in a GenericMessage with a non-String/non-byte[] payload
     GenericClass<String> genericClass = new GenericClass<>();
-    genericClass.id = UUID.randomUUID().toString();
     try {
       RqueueMessageUtils.buildPeriodicMessage(
           messageConverter2,