Add Apple fine print to native donate form

[tonisevener]

Phabricator:
https://phabricator.wikimedia.org/T345846

Notes

Added "Apple is not in charge of raising money for this purpose." fine print to the bottom of the native donate form. Marking as hold until design review is complete.

Test Steps

1. Log into iOS Sandbox Tester Apple ID (see 1Password) in test device iOS Settings. Do not enable 2 factor auth.
2. In Wallet app, add Test Apple Pay card.
3. Change device region to NL or IT.
4. On Staging scheme, fresh install and launch app.
5. On Explore feed, background, then foreground, then pull to refresh on Explore feed to fetch latest campaigns.
   In Settings, you should now see a "Donate to Wikipedia" cell, tap it. Tap "Donate with Apple Pay" option in alert view.
6. Note new fine print on donate form.

Screenshots

[staykids]

Very sweet seeing this native Apple Pay stuff come together! I created a new sandbox acct. for myself to test with to see more of the end to (almost) end process myself.