JAVA-4611: Update deprecations in spring-boot-rest module

spring-boot-rest/src/test/java/com/baeldung/controllers/ExamplePostControllerRequestIntegrationTest.java

@@ -33,7 +33,7 @@ public class ExamplePostControllerRequestIntegrationTest {
 
     @Before
     public void preTest() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
         mockMvc = MockMvcBuilders
           .standaloneSetup(exampleController)
           .build();

spring-boot-rest/src/test/java/com/baeldung/controllers/ExamplePostControllerResponseIntegrationTest.java

@@ -34,7 +34,7 @@ public class ExamplePostControllerResponseIntegrationTest {
 
     @Before
     public void preTest() {
-        MockitoAnnotations.initMocks(this);
+        MockitoAnnotations.openMocks(this);
         mockMvc = MockMvcBuilders
           .standaloneSetup(exampleController)
           .build();

spring-boot-rest/src/test/java/com/baeldung/web/StudentControllerIntegrationTest.java

@@ -8,12 +8,10 @@ import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.http.MediaType;
 import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
-import org.springframework.web.server.MediaTypeNotSupportedStatusException;
 
 import com.baeldung.web.controller.students.Student;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;