Unmark updateCheckTimerHandle as state()

The timer handle is internal logic, it doesn't affect displayed data and
shouldn't cause an update of the component.

Currently the value of the handle gets updated every `update_delay`
seconds causing lit component update process.

Release-Notes: skip
Change-Id: Ie00f58729feb6863d4cf460d44e5247c97c91153
(cherry picked from commit df666809decec18d552b9d9a70d3638db6370d60)
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
index ed42b3b..0d742de 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.ts
@@ -324,7 +324,6 @@
   @state()
   replyDisabled = true;
 
-  @state()
   private updateCheckTimerHandle?: number | null;
 
   @state() editMode = false;