[3.x] Address fixes

[Jade-GG]

1. Don't use the setExisting query. The setExisting query only sets the customer_address_id. This works fine in the core due to the way it combines the customer address select box and the address fields.
   However, this line should not have been copied over into the checkout theme, as this now causes a bug where you cannot change an address with a customer_address_id in the checkout because it will use the wrong query and not actually care about anything you set in the address form
2. Fix cart queries to use the fragment. This was already partially done in [3.x] Fix getCart query & styling for payment step & button label #148 but apparently there were 4 more. These have been fixed.
3. Fix the checkmark

[royduin]

Conflicts 😇