public async Task <ActionResult <ProjectDTO> > AddTodoItemToProject(int pid, TodoItem todoItem)
        {
            // https://stackoverflow.com/questions/48359363/ef-core-adding-updating-entity-and-adding-updating-removing-child-entities-in
            try
            {
                var project = await _repository.AddTodoItemToProjectAsync(pid, todoItem);

                return(CreatedAtAction(nameof(GetProject), new { id = project.Id }, project));
            }
            catch (ObjectNotFoundException)
            {
                return(NotFound());
            }
        }