Configures an OpenLayers ImageStaticSource object from the provided
Mapbox GL style object.
@param {Object} glSource The Mapbox GL map source of type 'image'.

@returns {Object} Configured OpenLayers ImageStaticSource.
function configureImageSource(glSource) {
  const coords = glSource.coordinates;
  return new ImageStaticSource({
    url: glSource.url,
    imageExtent: [coords[0][0], coords[3][1], coords[1][0], coords[0][1]],
    projection: 'EPSG:4326',
  });
}