Cookie Driver: Checkout Completion not clearing cart from browser

[duncanmcclean]

I'm yet to confirm it myself but by the looks of things, in #382, the cookie driver seems to not remove the cart cookie from the customer's browser after checkout has been complete.

The linked discussion mentions it happening with the Mollie gateway after its redirect but I'm guessing it probably happens for on-site gateways, like Stripe as well.

How to reproduce

1. Configure site to use CookieDriver
2. Add item to cart
3. Go to checkout and enter payment information
4. User will then be redirected.
5. Go to cart page, and see items remaining in user's cart.

What I expected

Like what happens with the session driver, after checkout, the customer's cart should be removed from their browser.

Environment

I'm assuming this happens with the latest version of v2.2.

[duncanmcclean]

Took me ages to figure out but it should be fixed for the next release.

[duncanmcclean]

Fixed in v2.2.14!