Add a single "Loading" state scenario for a generic KMW tile component.

assets/js/components/KeyMetrics/MetricTileNumeric.stories.js

@@ -95,6 +95,21 @@ Loading.args = {
  previousValue: 0,
  loading: true,
 };
+// Since the "Loading" state is the same for all KMW tiles, this is the sole scenario
+// and should not be added to any other generic `MetricTile___` or KMW component.
+Loading.scenario = {
+ label: 'KeyMetrics/MetricTileNumeric/Loading',
+};
+Loading.decorators = [
+ ( Story ) => {
+ // Ensure the animation is paused for VRT tests to correctly capture the loading state.
+ return (
+ <div className="googlesitekit-vrt-animation-paused">
+ <Story />
+ </div>
+ );
+ },
+];
 
 export default {
  title: 'Key Metrics/WidgetTiles/MetricTileNumeric',