fix(webapp): remove top padding from the open side menu notification

The expanded notification card now sits flush to the top of its slot
(p-2 pt-0); the collapsed bell icon is unchanged.

Author: samejr

apps/webapp/app/components/navigation/NotificationPanel.tsx

@@ -121,7 +121,7 @@ export function NotificationPanel({
 
   return (
     <Popover>
-      <div className={isCollapsed ? "p-1" : "p-2"}>
+      <div className={isCollapsed ? "p-1" : "p-2 pt-0"}>
         {isCollapsed ? (
           <SimpleTooltip
             asChild