Use response models

[gadomski]

Related Issue(s):

• Closes Response models are not being used to validate responses #461

Description:

WIP PR to allow response models to actually be used to validate outgoing objects. Currently just has a failing test.

We currently wrap every response in a Response of some sort:

stac-fastapi/stac_fastapi/api/stac_fastapi/api/routes.py

Lines 18 to 25 in fc06ac3

	def _wrap_response(resp: Any, response_class: Type[Response]) -> Response:
	if isinstance(resp, Response):
	return resp
	elif resp is not None:
	return response_class(resp)
	else: # None is returned as 204 No Content
	return Response(status_code=HTTP_204_NO_CONTENT)

This short-circuits the response model system in FastAPI: https://github.com/tiangolo/fastapi/blob/40df42f5c7d92815ceeb546df60256dacb3eed57/fastapi/routing.py#L241-L244

To fix, we'll need to pass through raw JSON objects as-is if response models are enabled.

PR Checklist:

• Code is formatted and linted (run pre-commit run --all-files)
• Tests pass (run make test)
• Documentation has been updated to reflect changes, if applicable, and docs build successfully (run make docs)
• Changes are added to the CHANGELOG.

[gadomski]

Closing as OBE #555.