Add note about new copy and print buttons

What does this MR do?

In !49078 (merged) we updated the 2FA recovery codes view to require users to either copy, download, or print codes before being able to proceed. The idea is to hopefully encourage users to save their recovery codes.

This MR adds a note about the new "Copy codes", "Download codes", and "Print codes" buttons.

Screenshots for context

Desktop

Page	Before	After
Recovery codes
Recovery codes - Proceed enabled	N/A
Account after clicking "Proceed"

Mobile

Page	Before	After
Recovery codes
Account after clicking "Proceed"

Related issues

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