#7664608 Purchases: Refactor cancel purchase page to use new layout

Proposed Changes

Restyle Cancel Purchase page, using a new layout with a right sidebar and a list of features for WPCom plan.
P2: pebzTe-aB-p2

Design

Before

After

Specific cases

The following are specific cases, for which the page layout changes, as they make use of the usual CancelPurchase component.

Domains

Jetpack products

One-time purchases

Testing Instructions

1. Visit /me/purchases
2. Select a purchase
3. Cancel the purchase
4. Verify the page layout is changed.
5. Verify the Loading Placeholder is updated with the new design
6. Verify the Feature Set for WPCom Plans are properly shown
7. Verify that the copy for Subscriptions accordingly with the design
8. Verify the cancel functionality works properly
9. Verify the responsive behaviour
10. The following are specific cases (see Specific cases section):
    • Domains
    • Jetpack products
    • One-Time purchases

Pre-merge Checklist

• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the “[Status] String Freeze” label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the “[Status] Needs Privacy Updates” label if this pull request changes what data or activity we track or use (p4TIVU-ajp-p2)?