Fix backup not resuming after closed and reopen (#266)

* Fixed app not resuming backup after closing and reopening the app

* Fixed cosmetic effect of backup button doesn't change state right away after pressing start backup

* Fixed grammar

* Fixed deep copy problem that cause incorrect asset count when backing up

* Format code

mobile/lib/shared/providers/asset.provider.dart

@@ -45,7 +45,7 @@ class AssetNotifier extends StateNotifier<List<ImmichAsset>> {
         }
       }
     }
-    
+
     try {
       await PhotoManager.editor.deleteWithIds(deleteIdList);
     } catch (e) {