style: 统一下拉与加载指示器

test/library/favorites_page_test.dart

@@ -99,7 +99,8 @@ void main() {
     );
     await tester.drag(find.byType(ListView), const Offset(0, 240));
     await tester.pump();
-    expect(find.text('Refreshing…'), findsOneWidget);
+    expect(find.byKey(const Key('pull-refresh-indicator')), findsOneWidget);
+    expect(find.text('Refreshing…'), findsNothing);
     await tester.pumpAndSettle();
 
     await tester.tap(find.byKey(const Key('favorite-remove-signal')));