make hello messages more clear

src/my_node.cpp

@@ -20,5 +20,5 @@ MyNode::~MyNode()
 
 void MyNode::hello_node()
 {
-	UtilityFunctions::print("Hello Node!");
+	UtilityFunctions::print("Hello GDExtension Node!");
 }

src/my_singleton.cpp

@@ -31,5 +31,5 @@ MySingleton::~MySingleton()
 
 void MySingleton::hello_singleton()
 {
-	UtilityFunctions::print("Hello Singleton!");
+	UtilityFunctions::print("Hello GDExtension Singleton!");
 }