Add related links and contact information to Curated lists

We have had requests to add related links to curated lists, like those that can be found in the right rail on the service detail page: mass.gov/service-details/massachusetts-state-retirement-board-meetings-msrb

We have also heard that users would like to add contact information to curated lists.

**JIRA ticket:** DP-6388

Review the example service detail page in the issue and the linked JIRA ticket DP-6388 first. Determine how curated lists currently represent related links and contact information, then define the expected list fields and presentation; done means both requested additions are supported for curated lists.

Written by the indexing model from the issue text.