Search returning null features for searches with no results about pgstac

[lossyrob]

These tests:

FAILED clients/test_postgres.py::test_delete_item - TypeError: 'NoneType' object is not iterable
FAILED resources/test_item.py::test_delete_item - TypeError: 'NoneType' object is not iterable
FAILED resources/test_item.py::test_item_search_by_id_no_results_post - TypeError: 'NoneType' ...
FAILED resources/test_item.py::test_item_search_get_query_extension - TypeError: 'NoneType' ob...

[vincentsarago]

I think this is due to fields

select s from search('{"collections":["something"]}') s;
>>> {"next": null, "prev": null, "type": "FeatureCollection", "context": {"limit": 10, "matched": 0, "returned": 0}, "features": []}

select s from search('{"collections":["something"],"fields":{"include":["id"]}}') s;
>>>  {"next": null, "prev": null, "type": "FeatureCollection", "context": {"limit": 10, "matched": 0, "returned": 0}, "features": null}

@lossyrob could you point out which tests were failing ?

[vincentsarago]

fixed in #46