support omission of resource content on instance-level history interaction

[lmsurpre]

Is your feature request related to a problem? Please describe. As of https://github.com/IBM/FHIR/issues/2026 we support conditionally omitting the resource content from a system or type-level history interaction (based on the "return" component of the "Prefer" header).

However, this feature is not supported for instance-level history and that feels a bit inconsistent.

Describe the solution you'd like When the client preference of return=minimal is set, omit the resource content from the instance-level history response.

Describe alternatives you've considered

Acceptance Criteria

1. GIVEN a server with resource Patient/123 WHEN client invokes GET [base]/Patient/123/_history AND sets Prefer: return=minimal THEN the entries in the history bundle response should not contain any Entry.resource elements

Additional context Consider adding this support for read / vread as well. Probably worth checking our support for the HTTP HEAD method type... this feature is more useful if that HEAD response doesn't return ETag of LastModified.

[lmsurpre]

To just omit it from the response is pretty simple. To prevent reading it from the db, it might take some work, but is probably worth looking into (for performance).