fix: visual bug on board accessory

frontend/appflowy_flutter/lib/plugins/database_view/widgets/card/container/accessory.dart

@@ -66,7 +66,10 @@ class CardAccessoryContainer extends StatelessWidget {
     return Container(
       clipBehavior: Clip.hardEdge,
       decoration: decoration,
-      child: child,
+      child: ClipRRect(
+        borderRadius: const BorderRadius.all(Radius.circular(4)),
+        child: child,
+      ),
     );
   }
 }