List published versions

{  "items": [    {      "id": "string",      "project_id": "string",      "version": "string",      "spec_digest": "string",      "status": "string",      "release_notes": "string",      "published_by": "string",      "published_at": "2019-08-24T14:15:22Z",      "deprecated": true,      "deprecated_at": "2019-08-24T14:15:22Z",      "deprecation_reason": "string"    }  ]}

{  "error": {    "code": "string",    "message": "string"  }}