Hide Advanced Settings button when Brave Payments is disabled

[willy-b]

• Submitted a ticket for my issue if one did not already exist. (fixes issue Advanced setting button should be hidden when payments is disabled #4790)
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).

Most of the base tests in test/components/ledgerPanelTest.js are failing for me (e.g. enabling / disabling payments). I'm working on this.

• Ran git rebase -i to squash commits (if needed).

Test Plan:

1. Open Brave
2. Open Brave Preferences -> Payments tab
3. When Payments is disabled, observe that there is no "Advanced Settings" button in upper right
4. Click the Payments toggle, observe "Advanced Settings" appears when Payments are enabled
5. Click toggle again and confirm the "Advanced Settings" button is hidden again

fixes #4790

[bsclifton]

LGTM 😄 I tested it out locally too, works great