Make shopping cart checkout button red

[kylexrich]

Summary

• change the Shopping Cart checkout button background from black to the existing hot red theme color
• preserve the button's layout, label, and checkout behavior

Validation

• Revyl remote iOS rebuild completed successfully
• device instruction result: Instruction step success while asserting the Shopping Cart CHECKOUT button has a clearly red capsule-shaped background

Before

Shopping Cart checkout button before: black background

After

Shopping Cart checkout button after: red background

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