New Choose a wallet service modal should have Uphold privacy-policy link

[stephendonner]

Description

New Choose a wallet service modal should have Uphold privacy-policy link

Credit goes to @LaurenWags who pointed this out to me - I should've caught it when verifying #16178

Steps to Reproduce

1. launch Brave using --enable-logging=stderr --vmodule="*/variations/*"=6,"*/bat-native-ledger/*"=6,"*/brave_rewards/*"=6,"*/bat-native-ads/*"=6,"*/bat-native-confirmations/*"=6,"*/brave_ads/*"=9,"*/brave_user_model/*"=6 --brave-ads-staging --brave-ads-debug --rewards=staging=true,reconcile-interval=3
2. click on the BAT icon
3. click on Start using Rewards
4. click Skip for now
5. click Done
6. click on Verify Wallet (brave://rewards/#verify)
7. click Continue >
8. click on Uphold
9. look at the resulting change to the modal

Actual result:

The modal correctly adds the minimum-balance-Uphold message and Continue to login link, but neglects adding the Uphold privacy-policy link in the bottom Note: paragraph.

Expected result:

Per the mockup in the security/privacy review (https://github.com/brave/security/issues/473#issuecomment-856294892), the Choose a wallet service model should have an Uphold privacy policy link (https://uphold.com/en/legal/privacy-policy?)

Reproduces how often:

100%

Brave version (brave://version info)

Brave	1.27.77 Chromium: 91.0.4472.114 (Official Build) beta (x86_64)
Revision	4bb19460e8d88c3446b360b0df8fd991fee49c0b-refs/branch-heads/4472@{#1496}
OS	macOS Version 11.4 (Build 20F71)

/cc @codybanxs @Miyayes @zenparsing

[zenparsing]

@codybanxs @Miyayes We may have discussed this previously, but with the current design we won't be able to display a link to the wallet provider's privacy policy, since the user has not yet selected a provider. If the user has the minimum BAT amount required by the provider, then they'll be taken directly to the provider's login screen when they press the button.