#7015716 Checkout: Show refund periods for each product if DIFM Lite is in cart

Changes proposed in this Pull Request

The checkout order summary does not correctly show the refund period when products have different refund periods. For example, in a cart with a Premium Plan and DIFM Lite, the refund period is shown as 14 days. However, the DIFM Lite product has a refund period of 2 days.

This change shows the refund periods for each product in the cart so that there is no confusion when the user is buying products with different refund periods. However, this is enabled only if a DIFM Lite product is in the cart. Enabling this for all carts would require more testing and experimentation.

Testing instructions

Testing with DIFM Lite in cart

• Start from the DIFM signup flow by navigating to /start/do-it-for-me. On the domains step, choose a paid domain.
• On the checkout screen, confirm that the order summary (right sidebar) shows the refund period for all 3 products (WPCOM Plan, DIFM Lite and domain registration).
• Add another domain to this cart. You can do this by going to /domains/add/<site slug>. The site slug can be found in the URL on the checkout screen.
• On the checkout screen, confirm that the order summary (right sidebar) shows the refund period for the 3 unique products (WPCOM Plan, DIFM Lite and domain registration).
  

Testing without DIFM Lite in cart

• Test the checkout screen for these scenarios:

Test Case	Expected Output	Screenshot
Plan and multiple domains in cart.	Money back guarantee
Plan and single domain in cart.	Money back guarantee
Only plan in cart.	14-day money back guarantee (7 days if it’s a monthly plan)
Only domain in cart.	4-day money back guarantee