public async Task Test_Get_All_Customers()
        {
            using (var client = new CustomerContollerTest().Client)
            {
                var response = await client.GetAsync("/api/customers");

                response.EnsureSuccessStatusCode();

                response.StatusCode.Should().Be(HttpStatusCode.OK);
            }
        }
        public async Task Test_Post_Customer_NullLastName()
        {
            using (var client = new CustomerContollerTest().Client)
            {
                var response = await client.PostAsync("/api/customers"
                                                      , new StringContent(
                                                          JsonConvert.SerializeObject(new Customer()
                {
                    FirstName = "Test",
                    LastName = null,
                    DateOfBirth = DateTime.Now,
                    Salary = 30000
                }),
                                                          Encoding.UTF8,
                                                          "application/json"));

                response.StatusCode.Should().Be(HttpStatusCode.BadRequest);
            }
        }