update use_reducer docs

Author: Pascal-So

packages/yew/src/functional/hooks/use_reducer.rs

@@ -330,8 +330,13 @@ where
 /// implement a `Reducible` trait which defines the associated `Action` type and a
 /// reducer function.
 ///
-/// This hook will always trigger a re-render upon receiving an action. See
-/// [`use_reducer_eq`] if you want the component to only re-render when the state changes.
+/// This hook will trigger a re-render whenever the reducer function produces a new `Rc` value upon
+/// receiving an action. If the reducer function simply returns the original `Rc` then the component
+/// will not re-render. See [`use_reducer_eq`] if you want the component to first compare the old and
+/// new state and only re-render when the state actually changes.
+///
+/// To cause a re-render even if the reducer function returns the same `Rc`, take a look at
+/// [`use_force_update`].
 ///
 /// # Example
 /// ```rust