Change getUid return type from number to string

src/ol/renderer/vector.js

@@ -38,7 +38,7 @@ const GEOMETRY_RENDERERS = {
  * @return {number} Order.
  */
 export function defaultOrder(feature1, feature2) {
-  return getUid(feature1) - getUid(feature2);
+  return parseInt(getUid(feature1), 10) - parseInt(getUid(feature2), 10);
 }