How to make mockmvc work with a different actuator port?

Question

My code:

@SpringBootTest
@AutoConfigureMockMvc
public class ActuatorTests {


    @Autowired
    private MockMvc mockMvc;

    @Test
    public void testActuator() throws Exception {

        mockMvc.perform(get("/actuator/health/liveness"))
                .andExpect(status().isOk());
    }
}

works till I change the port with management.server.port=... . How can I modify it to make it work with a different port in Spring Boot 2.3?