public DeleteProductCommandHandler(IProductRepository productRepository, ISellerProductRepository sellerProductRepository)
 {
     _productRepository       = productRepository;
     _sellerProductRepository = sellerProductRepository;
 }
 public AddProductToSellerCommandHandler(IProductRepository productRepository, ISellerProductRepository sellerProductRepository)
 {
     _productRepository       = productRepository;
     _sellerProductRepository = sellerProductRepository;
 }