Simulate failing test

backend/src/test/java/core/users/UserRepositoryTests.java

@@ -31,7 +31,7 @@ public class UserRepositoryTests {
         userRepository.save(new User(1L,"FawKes100", "mail@fawkes100.de", "123456"));
 
         Optional<User> findResult = userRepository.findByUsername("FawKes100");
-        assertTrue(findResult.isPresent());
+        assertFalse(findResult.isPresent());
         assertEquals(new User(1L, "FawKes100", "mail@fawkes100.de", "123456"),findResult.get());
     }
 }