bitwarden/src/Core/Services/NoopImplementations/NoopMailDeliveryService.cs

using System.Threading.Tasks;
using Bit.Core.Models.Mail;

namespace Bit.Core.Services
{
    public class NoopMailDeliveryService : IMailDeliveryService
    {
        public Task SendEmailAsync(MailMessage message)
        {
            return Task.FromResult(0);
        }
    }
}