Tests purchase process on https://www.saucedemo.com
Provide just the item names as list of strings, test suite will count actual cart value. Check if number of items is displayed on the button in the top right corner.
Check if the names and prices are correct.
Fill the form and proceed with the purchase.
Make sure that the total amount to be paid is equal to the sum of all chosen items.
Check if "thank you" message is displayed. Use "go back home" button.
