Be more flexible with qnode categories

[patrickkwang]

This query works:

{
    "message": {
        "query_graph": {
            "nodes": {
                "n0": {
                    "ids": [
                        "MESH:D056487"
                    ],
                    "categories": [
                        "biolink:DiseaseOrPhenotypicFeature"
                    ]
                },
                "n1": {
                    "categories": [
                        "biolink:DiseaseOrPhenotypicFeature"
                    ]
                }
            },
            "edges": {
                "e01": {
                    "subject": "n0",
                    "object": "n1",
                    "predicates": [
                        "biolink:has_real_world_evidence_of_association_with"
                    ]
                }
            }
        }
    }
}

But if we replace n0 categories with ["biolink:Disease"], which is true according to the node normalizer, we get no results.