public async Task Cannot_delete_SiteManager_when_it_not_existing()
        {
            const string SITE_MANAGER_ID = "EMP100";

            using (var context = new ProcurementDbContext(ContextOptions))
            {
                SiteManagersController siteManagersController = new SiteManagersController(context);

                var result = await siteManagersController.DeleteSiteManager(SITE_MANAGER_ID);

                var viewResult = Assert.IsType <ActionResult <SiteManager> >(result);
                Assert.IsNotType <SiteManager>(viewResult.Value);
                var response = Assert.IsType <NotFoundResult>(viewResult.Result);
                Assert.Equal(404, response.StatusCode);
            }
        }
        public async Task Can_delete_SiteManager_by_Id()
        {
            const string SITE_MANAGER_ID = "EMP1";

            using (var context = new ProcurementDbContext(ContextOptions))
            {
                SiteManagersController siteManagersController = new SiteManagersController(context);

                var result = await siteManagersController.DeleteSiteManager(SITE_MANAGER_ID);

                var viewResult = Assert.IsType <ActionResult <SiteManager> >(result);
                var model      = Assert.IsType <SiteManager>(viewResult.Value);

                Assert.Equal(SITE_MANAGER_ID, model.StaffId);
            }
        }