[Mobile Payments] Show last4 and cardBrand on Refund Confirmation with Stripe gateway

[joshheald]

Split from #5976

Awaiting either:

• an API endpoint for fetching charge details equivalent to /payments/charges/ from the Stripe Gateway pdfdoF-ru-p2
• or the addition of required fields to Order.meta_data. p91TBi-7wE-p2

[jaclync]

Maybe we can move this issue out of the 🇨🇦 milestone since we only support WCPay for the release? (ref pdfdoF-D1-p2)

[joshheald]

Yeah it would make sense to treat Stripe Gateway as a separate project. I'll make a new one as a bucket for issues like this one...