Updated test to include more assertions

CartTests.java

@Test
public void test_add_to_cart(){
  String product = "TOKYO TALKIES";
  String color = "Red";
  String size = "M";
  int quantity = 2;

  productPage.setColor(color);
  productPage.setSize(size);
  productPage.setQuanity(quantity);

  productPage.addToCart();
  cart = productPage.goToCart();
  
  assertTrue(cart.isProductInCart(product));
  assertEquals(cart.getColor(product), color);
  assertEquals(cart.getSize(product), size);
  assertEquals(cart.getQuantity(product), quantity);
  assertEquals(cart.getPrice(product), "₹100.00");
  assertEquals(cart.getTotal(product), "₹200.00");
  assertEquals(cart.getNumberOfItems, 1);
}