Make "Hide Brave" translatable

[luixxiul]

• 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).

Closes #3983

Auditors: @aekeus

Test Plan:

1. Open Brave on Mac
2. Click "Brave" next to the apple icon on the menu bar
3. Make sure "Hide Brave" exists

[bbondy]

++