Builder Pattern useful with Setter-methods?

So I have a webproject with Hybris, Spring and so on.

I have some classes, which are autogenerated. Let's say I have one modelclass, which is autogenerated and inherits from another class some methods, to set fields.

When writing Unit-tests, is it useful to start using the Builder pattern? Because the thing is, I don't have a constructor, like Employee(int id, String name) and so on, I only have the inherited methods to set them (setId(int id) and so on).

So when I would write a Builder class for this model for example, I would have the methods .withId(int id) and .withName(String name) and the build()-method, where I would run the setter-methods.

so in the end in my test-class I would have:

EmployeeBuilder eb = new EmployeeBuilder();
Employee emp = eb.withId(123)
                 .withName("John")
                 .build();

But since I already have Setter-Methods I normally have:

Employee emp = new Employee();
emp.setId(123);
emp.setName("John");

So is it really worth the effort in this case? Or is there something I have not really understood?

Thanks!