Support compartment search via POST

[tbieste]

Describe the solution you'd like
Would like to be able perform compartment search via POST:

POST [base]/[Compartment]/[id]/[type]/_search{?[parameters]{&_format=[mime-type]}}

Describe alternatives you've considered
N/A

Acceptance Criteria
1.
GIVEN Resources exist in compartment on FHIR Server
WHEN Compartment search via POST is performed
THEN Search successful returns matching resources

Additional context
Compartment search is supported.
Search via POST is supported.
But compartment search via POST is not supported.

Note: don't forget to add it to the generated swagger/openapi too (a la #1846 )

[michaelwschroeder]

Running against my local server with the latest codebase, I have performed equivalent compartment searches using GET and POST methods via Postman and have verified the results returned are equivalent.