Use list markup for cart line items

[spencercanner]

• Wrap cart line item list in a <ul />
• Wrap each line item in a <li />
• Add a list role to the <ul/ > to address a Safari VoiceOver bug
  • I didn't opt for the solution posted in MDN since it's more of a hack rather than a permanent solution. This was adding whitespace above the line item product title

To 🎩

• Navigate a virtual cursor to a cart with line items
• Verify that the screen reader announces the line items as a list

Browsers:

• Safari - Mac - VoiceOver
• Firefox - Windows - NVDA

• Sanity check that cart doesn't look visually different

Browsers:

• Chrome - Mac
• Safari - Mac
• Firefox - Mac
• Edge - Mac
• Legacy Edge - Windows
• Edge - Windows
• Chrome - Windows
• Firefox - Windows
• Safari - iOS
• Chrome - Android