Feature request: Allow setting up donations block for a separate Stripe or PayPal account

### Impacted plugin

Jetpack

### What

Allow setting up donations block for a separate Stripe or PayPal account

### How

At the moment, once I connect a Stripe account to my website, it will be used for all revenue blocks (payment buttons, donation forms, etc).

But users may want to have a different stripe or Paypal account linked to another organization to donate to them directly, as was the case for this user 7586477-zd-a8c.
It would be nice to have this feature. Something anyone could set up to collect donations without the use of a plugin.

The issue identifies the Jetpack donations block and the need for a separate Stripe or PayPal account, but it names no files, tests, or entry points. Start by locating the donations block and its current revenue-account setup, then determine how account selection is configured. Done means users can independently configure a donation account without changing the account used by other revenue blocks.

Written by the indexing model from the issue text.