Update Link page to remove references to OMB M-17-06

[sarah-sch]

Purpose of this issue

This issue closes #2474 reporting the outdated reference to OMB M-17-06 on the USWDS Link component page. Here, we are outlining work related to updating the Link page to remove these outdated policy references.

Summary of team's discussion of this issue

@finekatie updated the team on the state of the Link page on 2/28/2024. She shared this Mural board analyzing opportunities for updates on the Link page.

The team discussed the following points on 2/28/2024, which should guide page updates:

• Remove references to M-17-06 because M-23-22 rescinds the previous memo. OK to mention that M-17-06 rescinds M-23-22 in copy.
• Some of the guidance based on M-17-06 is still solid and not addressed by M-23-22, so it is ok to keep those best practices in our content.
• Restructure/reorganize "musts" as "shoulds": Guidance should generally remain the same, but where we are currently talking about what you "must" do and it is not referenced in M-23-22, it should become what you "should do."
• We do NOT need to replace the M-17-06 accordion with a M-23-22 accordion
• Under "Additional Information" heading remove old policy and add new one

Work to be done

• [ ] Draft copy updates for Links page
• [ ] Fed approval of copy updates
• [ ] Create a pull request for copy updates
• [ ] Fed final review