Fix use of sizeOnDisk

frontend/src/Series/Details/SeriesDetailsSeason.js

@@ -220,13 +220,16 @@ class SeriesDetailsSeason extends Component {
       onSearchPress
     } = this.props;
 
+    const {
+      sizeOnDisk = 0
+    } = statistics;
+
     const {
       episodeCount,
       episodeFileCount,
       totalEpisodeCount,
       monitoredEpisodeCount,
-      hasMonitoredEpisodes,
-      sizeOnDisk
+      hasMonitoredEpisodes
     } = getSeasonStatistics(items);
 
     const {