public IActionResult AddMaterial([FromForm] ProductMaterial model)
        {
            if (ModelState.IsValid)
            {
                int isAdded = _workshopRepository.AddMaterialToProduct(model);

                return(RedirectToAction(nameof(Edit), new { id = model.WSProductId }));
            }
            ProductMaterialCreationViewModel model1 = new ProductMaterialCreationViewModel()
            {
                ProductMaterial = model,
                Materials       = _workshopRepository.GetAllMaterials(),
                productId       = model.WSProductId
            };

            return(View(model1));
        }