Fix warnings with latest nightly

src/platform_impl/web/event_loop/runner.rs

@@ -15,7 +15,6 @@ use crate::window::WindowId;
 
 use std::{
     cell::{Cell, RefCell},
-    clone::Clone,
     collections::{HashSet, VecDeque},
     iter,
     ops::Deref,

src/platform_impl/web/web_sys/event.rs

@@ -4,7 +4,6 @@ use crate::keyboard::{Key, KeyLocation, ModifiersState, NamedKey, PhysicalKey};
 
 use smol_str::SmolStr;
 use std::cell::OnceCell;
-use std::convert::TryInto;
 use wasm_bindgen::prelude::wasm_bindgen;
 use wasm_bindgen::{JsCast, JsValue};
 use web_sys::{KeyboardEvent, MouseEvent, PointerEvent, WheelEvent};