Why session scope bean is the same for different mock session in tests

I'm trying to test session scoped bean in Spring-boot but i've encountered problem. I've created two MockHttpSession and try to inject them into controller method, which then will add to them scoped bean. If i run application those beans are different in each scope, but when i try to test it, the object is the same. Here is my test:

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class ObserverSessionScopedIT {

@Autowired
private
ObserverController controller;

@Rule
public TemporaryFolder temporaryFolder = new TemporaryFolder();

@Test
public void sessionScope() throws Exception {

    MockHttpSession sessionFirst = new MockHttpSession();
    MockHttpSession sessionSecond = new MockHttpSession();

    sessionFirst.changeSessionId();
    sessionSecond.changeSessionId();

    controller.startObserving(temporaryFolder.getRoot().getAbsolutePath(), sessionFirst);
    controller.startObserving(temporaryFolder.getRoot().getAbsolutePath(), sessionSecond);

    Subscriptions subscriptionsFirst = (Subscriptions) sessionFirst.getAttribute("Subscriptions");
    Subscriptions subscriptionsSecond = (Subscriptions) sessionSecond.getAttribute("Subscriptions");

    Assertions.assertThat(subscriptionsFirst).isNotSameAs(subscriptionsSecond);

}

and here is how i menage it in controller:

private static final String SUBSCRIPTION = "Subscriptions";
(...)

@Autowired
private Subscriptions subscriptions;

@CrossOrigin
@RequestMapping(path = "/start", method = RequestMethod.POST)
@ResponseBody ResponseEntity<String> startObserving(@RequestBody String path, HttpSession httpSession) throws IOException {
     (...)
    httpSession.setAttribute(SUBSCRIPTION, subscriptions);
     (...)
    }

and this is definition of Subscriptions object:

@Service
@SessionScope
public class Subscriptions implements AutoCloseable{

Why i have two different objects while application works, but in test it's the same reference? I think it might be connected to context in test, but can i run tests with main application context?