NIAD-3130 - Add ConfidentialityCode support to ReferralRequest

[martin-nhs]

What

This PR updates the patient switching standard adapter to handle confidentiality codes. Specifically, if a confidentiality code with the value NOPAT is found in the ehrComposition or requestStatement, the meta.security field will be populated accordingly. If the confidentiality code has any value other than NOPAT, meta.security will NOT be added to the resource.

Why

More details can be found on the ticket.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• I have performed a self-review of my code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have updated the Changelog with details of my change in the UNRELEASED section if this change will affect end users
• A corresponding change has been made to the Mapping Documentation repository