Get all project categories

{
  "type": "array",
  "items": {
    "type": "object",
    "description": "A project category.",
    "properties": {
      "description": {
        "type": "string",
        "description": "The description of the project category."
      },
      "id": {
        "type": "string",
        "description": "The ID of the project category."
      },
      "name": {
        "type": "string",
        "description": "The name of the project category. Required on create, optional on update."
      },
      "self": {
        "type": "string",
        "format": "uri",
        "description": "The URL of the project category."
      }
    },
    "additionalProperties": false
  }
}