Fix the test method (#2491)

* Remove assertion before persist in test1

* Add back assertion after persist

spring-hibernate5/src/test/java/com/baeldung/hibernate/manytomany/HibernateManyToManyAnnotationMainIntegrationTest.java

@@ -47,8 +47,8 @@ public class HibernateManyToManyAnnotationMainIntegrationTest {
             Employee employee = new Employee(emp.split(" ")[0], emp.split(" ")[1]);
             assertEquals(0, employee.getProjects().size());
             employee.setProjects(projects);
-            assertNotNull(employee);
             session.persist(employee);
+            assertNotNull(employee);
         }
     }