Remove argument from use_hook closure (#496)

Also; update docs for said function

packages/fermi/src/hooks/init_atom_root.rs

@@ -4,7 +4,7 @@ use std::rc::Rc;
 
 // Initializes the atom root and retuns it;
 pub fn use_init_atom_root(cx: &ScopeState) -> &Rc<AtomRoot> {
-    cx.use_hook(|_| match cx.consume_context::<Rc<AtomRoot>>() {
+    cx.use_hook(|| match cx.consume_context::<Rc<AtomRoot>>() {
         Some(ctx) => ctx,
         None => cx.provide_context(Rc::new(AtomRoot::new(cx.schedule_update_any()))),
     })