Follow-up: Button styles consistent

[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).

Based on #5916 (comment) this fixes

• Margin-bottom of the brave wallet address

• Avoided button text from overflowing (l10n-friendly)

Auditors: @bradleyrichter

Test Plan:

1. Open about:preferences#payments
2. Make sure that there is margin-bottom set to the brave wallet address
3. Change the lang setting into Japanese
4. Make sure that the buttons on about:preferences#payments no longer overflow

[luixxiul]

I created the issue for QA: #6675