[Payment card / Subscription] Integrate “Subscription details” section with backend data

[MitchExpensify]

From this section of the doc: https://docs.google.com/document/d/1jXV_vIsOGZuL0dMiuXDWRETAFRX64ODVAhWPtiuFXT8/edit?pli=1&tab=t.0#bookmark=id.3ofmuddf4blc @fabioh8010

[fabioh8010]

Hi, I'm Fábio from Callstack - expert agency - and I would like to work on this issue.

[JKobrynski]

Hi, I'm Julian from Callstack - expert agency - and I would like to work on this issue.

[JKobrynski]

I think it has been resolved in #42975, the plan is already fetched from API and read from Onyx. The "Changing plan action" will be implemented in #43029 (a draft was internally approved). What do you think? Is there anything else backend related?

CC: @amyevans