Fix clippy::rc_buffer (#1728)

src/app.rs

@@ -459,8 +459,8 @@ where
 {
     fn into_factory(self) -> AppInit<T, B> {
         AppInit {
-            data: Rc::new(self.data),
-            data_factories: Rc::new(self.data_factories),
+            data: self.data.into_boxed_slice().into(),
+            data_factories: self.data_factories.into_boxed_slice().into(),
             endpoint: self.endpoint,
             services: Rc::new(RefCell::new(self.services)),
             external: RefCell::new(self.external),