message: [Visual Search API] Update encoding format documentation per PM request
diff: "type": "string"
  },
  "encodingFormat": {
  - "description": "Encoding format (e.g., mp3, mp4, jpeg, etc).",
  + "description": "Encoding format (e.g., png, gif, jpeg, etc).",
  "readOnly": true,
  "type": "string"
  },
  