public static WithoutNullabilityApplication CreateApplication(Guid? id = null)
        {
            var stubApplicationRepo = 
                new Mock<IRepository<ApplicationEntity>>(MockBehavior.Loose);
            stubApplicationRepo
                .Setup(e => e.Create(It.IsAny<ApplicationEntity>()))
                .Callback(() => NextId = Guid.NewGuid())
                .Returns(NextId);

            var application = 
                new WithoutNullabilityApplication(stubApplicationRepo.Object, id ?? Guid.Empty)
                    {
                        LastName = "Public", 
                        FirstName = "John", 
                        DateOfBirth = new DateTime(1991, 5, 7),
                    };
            
            return application;
        }
        public static WithoutNullabilityApplication CreateApplication(Guid?id = null)
        {
            var stubApplicationRepo =
                new Mock <IRepository <ApplicationEntity> >(MockBehavior.Loose);

            stubApplicationRepo
            .Setup(e => e.Create(It.IsAny <ApplicationEntity>()))
            .Callback(() => NextId = Guid.NewGuid())
            .Returns(NextId);

            var application =
                new WithoutNullabilityApplication(stubApplicationRepo.Object, id ?? Guid.Empty)
            {
                LastName    = "Public",
                FirstName   = "John",
                DateOfBirth = new DateTime(1991, 5, 7),
            };

            return(application);
        }