public Group GetGroupWithUsers(Guid id)
 {
     GroupWithUsersQuery query = new GroupWithUsersQuery(dbContext.Groups);
     return query.Execute(id);
 }
 public IReadOnlyCollection<User> GetGroupMembers(Guid groupId)
 {
     var query = new GroupWithUsersQuery(dbContext.Groups);
     return new UserMapper().Map(query.Execute(groupId).Users).ToList();
 }