message: Fixed error when using download with admin
diff: @@ -157,7 +157,7 @@ export class DownloadController {
  const course = await Course.findOne({_id: data.courseName});
  if (course.students.indexOf(user._id) !== -1 || course.courseAdmin === user._id ||
  - course.teachers.indexOf(user._id) !== -1) {
  + course.teachers.indexOf(user._id) !== -1 || user.role === 'admin') {
  if (!data.lectures.length) {
  throw new NotFoundError();
  