message: API: Add unit duplication lecture/course mismatch test
  This will fail until the associated DuplicationController bug is fixed.
diff: @@ -261,5 +261,21 @@ describe('Duplicate', async () => {
  result.status.should.be.equal(403);
  });
  +
  + it('should fail unit duplication when the given target lecture doesn\'t belong to the target course', async () => {
  + const unit = await FixtureUtils.getRandomUnit();
  + const targetCourse = await FixtureUtils.getCourseFromUnit(unit);
  + const teacher = await FixtureUtils.getRandomTeacherForCourse(targetCourse);
  + const otherCourse = await Course.findOne({_id: {$ne: targetCourse}});
  + const otherTargetLecture = await FixtureUtils.getRandomLectureFromCourse(otherCourse);
  +
  + const result = await chai.request(app)
  + .post(`${BASE_URL}/unit/${unit._id}`)
  + .set('Cookie', `token=${JwtUtils.generateToken(teacher)}`)
  + .send({courseId: targetCourse._id, lectureId: otherTargetLecture._id})
  + .catch((err) => err.response);
  +
  + result.status.should.be.equal(400);
  + });
  });
  });
  