Create e2e test with the full flow

[sorokinvj]

Lets create a cypress test that will check if user could indeed buy things from the shop:

• Lets use production url for a test - https://maria-antiques.vercel.app/
• Create a test that will add something in a cart, go to checkout, make a checkout, enter card details, buy, go back to the shop and check the page "Order successfull"
• Use stripe test card for checkout: 4242 4242 4242 4242, any future date, any cvv