Add Payments to Bravery system menu

[ayumi]

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

Close #3592

Auditors: @bradleyrichter @diracdeltas

Test Plan:

1. Disable Payments
2. Open OS menu "Bravery"
3. See menu item "Start using Brave payments..." -- click it
4. Tab opens to Prefs > Payments
5. Enable Payments
6. Close tab
7. Open OS menu "Bravery" again
8. Payments menu item now says "Brave payments"
9. Close and reopen Brave
10. Menu item still says "Brave payments"

[luixxiul]

#3675 should be applied here too I think

[ayumi]

@luixxiul i like that – i'd like to update it in a new PR

[bsclifton]

@ayumi does this also cover the hamburger menu? I know there is shared code (so it might 😄)

[ayumi]

@bsclifton yess

[diracdeltas]

++ thanks