Remove argument from use_hook closure (#496)

Also; update docs for said function

packages/hooks/src/use_shared_state.rs

@@ -61,7 +61,7 @@ impl<T> ProvidedStateInner<T> {
 ///
 ///
 pub fn use_context<T: 'static>(cx: &ScopeState) -> Option<UseSharedState<T>> {
-    let state = cx.use_hook(|_| {
+    let state = cx.use_hook(|| {
         let scope_id = cx.scope_id();
         let root = cx.consume_context::<ProvidedState<T>>();
 
@@ -173,7 +173,7 @@ where
 ///
 ///
 pub fn use_context_provider<T: 'static>(cx: &ScopeState, f: impl FnOnce() -> T) {
-    cx.use_hook(|_| {
+    cx.use_hook(|| {
         let state: ProvidedState<T> = Rc::new(RefCell::new(ProvidedStateInner {
             value: Rc::new(RefCell::new(f())),
             notify_any: cx.schedule_update_any(),