bregctl scaffold: re-link the configuration section folded into the journeys page

The bregctl scaffold's generated links no longer point at the configuration section that the documentation rewrite folded into the journeys page. Re-link once the docs release carrying that page is live; the scaffold-links test reads the docs pages, so it pins the target.

Origin: review of PR #850.

Start with the bregctl scaffold link generation and the scaffold-links test, which reads the documentation pages. Confirm the docs release containing the journeys page is live, then update the configuration link target and use the test to verify it points to that section.

Written by the indexing model from the issue text.