Update eventcart test to only test payment form

[mattwire]

Overview

There are two forms in the "checkout" phase of the eventcart. One which selects payments and prices and the final one which is the checkout where payment is taken.
The original implementation incorrectly set participants to "registered" on the first form while the refactored version uses Order API and correctly sets them to "Pending in Cart" until payment is taken when they are updated to Registered.

This updates the test to only check the "registered" status on completion of the second checkout (payment) form and will pass with both original and new implementations.

Before

Participants set as registered before payment, test validating that happens.

After

Test validating that participant is "registered" once payment has been made.

Technical Details

Explained above. Test change only.

Comments

[civibot]

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[eileenmcnaughton]

seems fine