Given a URI, returns the last segment of the URI, removing any path or query information.
Example:
//fileName will be"simple.czml";
const fileName = Cesium.getFilenameFromUri('/Gallery/simple.czml?value=true&example=false');
//fileName will be"simple.czml";
const fileName = Cesium.getFilenameFromUri('/Gallery/simple.czml?value=true&example=false');