SAP Guidance example and documentation

## User Story

In order to provide guidance for how SAP and data.gov integrate, metadata providers want guidance on how to implement in both DCAT-US1.1 and 3.0 metadata today.

## Acceptance Criteria

[ACs should be clearly demoable/verifiable whenever possible. Try specifying them using [BDD](https://en.wikipedia.org/wiki/Behavior-driven_development#Behavioral_specifications).]

- [ ] GIVEN a metadata provider utilizes SAP for private data sharing \
WHEN a metadata provider goes to resources.data.gov \
THEN clear documentation shows examples of best practices

## Background

[Any helpful contextual notes or links to artifacts/evidence, if needed]

## Security Considerations ([required](https://nvd.nist.gov/800-53/Rev4/control/CM-4))

[comment]: # "Our SSP says 'The Data.gov team ensures security implications are considered as part of the agile requirements refinement process by including a section in the issue template used as a basis for new work.' so please don't remove this section without care."
None

## Sketch

This should involve looking at current examples, and our UI, for any possible live working versions.
Would expect this to look like some type of accessURL directly to the SAP resource.

Start by reviewing the current examples and the UI at resources.data.gov, focusing on how SAP private data sharing and accessURL values are represented for DCAT-US 1.1 and 3.0. Done means the documentation presents clear, verifiable best-practice examples for both metadata versions, including a working SAP resource link where available.

Written by the indexing model from the issue text.