Fix timer not firing on Windows

If we set the control flow to Wait, winit will always wait even if we
set the control flow later to some smaller timeout in the AboutToWait
event.
Wait is the default anyway in winit 0.29 so this is not required

I'd say this is a bug in winit, but we can easily work it around

Fix #3875

internal/backends/winit/event_loop.rs

@@ -500,8 +500,6 @@ impl EventLoopState {
             }
 
             Event::NewEvents(_) => {
-                event_loop_target.set_control_flow(ControlFlow::Wait);
-
                 self.windows_with_pending_redraw_requests.clear();
                 ALL_WINDOWS.with(|windows| {
                     for (window_id, window_weak) in windows.borrow().iter() {