BAT Points updates for unsupported regions

[ryanml]

Fixes brave/brave-browser#6480
Fixes brave/brave-browser#6577

This implements the BAT Points language for regions where only anon wallets are allowed.

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Verified that these changes build without errors on
  • Android
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that these changes pass automated tests (unit, browser, security tests) on
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that all lint errors/warnings are resolved (npm run lint)
• Ran git rebase master (if needed).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.
• Request a security/privacy review as needed.
• Add appropriate QA labels (QA/Yes or QA/No) to include the closed issue in milestone
• Public documentation has been updated as necessary. For instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protection-Mode
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Custom-Headers
  • https://github.com/brave/brave-browser/wiki/Web-compatibility-issues-with-tracking-protection
  • https://github.com/brave/brave-browser/wiki/QA-Guide

Test Plan:

1. Enable rewards
2. Wait for initilization
3. Close browser
4. Open Preferences file and search for countryid_at_install
5. Replace current value with 19024
6. Restart Browser
7. Claim a grant
8. Confirm that the grant claim shows "BAT Points" instead of BAT
9. Tip a couple of sites
10. Confirm that the wallet view in brave://rewards adheres to spec for bat points
11. Confirm that the panel adheres to spec for bat points

Reviewer Checklist:

• New files have MPL-2.0 license header.
• Request a security/privacy review as needed.
• Adequate test coverage exists to prevent regressions
• Verify test plan is specified in PR before merging to source

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on.
• All relevant documentation has been updated.

[NejcZdovc]

CI passed except of lint because of a known thing. Will restart CI just for mac as CI lint should be fixed now

[wmazoni]

When will BAT come to Brazil?

[NejcZdovc]

CI is failing on non related tests.

[kjozwiak]

Went through the following verifications using 0.73.42 CR: 78.0.3904.70 before approving . and uplifting both #3810 and #3809:

• went through and verified the STR/Cases outlined under BAT Points updates for unsupported regions #3751 (comment)
• ensured that setting the machines region to Japan correctly set "countryid_at_install":19024 via the Preferences file and launched the correct UI

There's certain parts of the UI that still mention BAT & Tokens but these will be addressed via the following issues:

• BAT Points follow-up to #6480 - Changes for Japan brave-browser#6654 (comment)
• BAT Points text needed on BR slide of desktop onboarding flow brave-browser#6602
• Change "no tokens" messaging on BR panel for BAT Points regions brave-browser#6604

Went through the following UI and ensured that BAT Points was being used as per https://docs.google.com/document/d/1Vf9rFeSEPx8KbZYzw_rCyMq8iv5AExU0fhnv3Q6bZe0/edit#heading=h.n61l82sr1zxg: