Sets style source properties. This method can be used to perform batch update for a style source properties. The structure of a provided `properties` value must conform to a format for a corresponding [source type](https://docs.mapbox.com/mapbox-gl-js/style-spec/sources/). Modification of a source [type](https://docs.mapbox.com/mapbox-gl-js/style-spec/sources/#type) is not allowed.
Return
A string describing an error if the operation was not successful, empty otherwise.