chore: Adjust comment, unused using

src/Uno.UI.RuntimeTests/Tests/Windows_UI/Given_WeakEventHelper.cs

@@ -5,7 +5,6 @@
 using System.Runtime.CompilerServices;
 using System.Text;
 using System.Threading.Tasks;
-using Microsoft.UI.Xaml.CustomAttributes;
 using Uno.Buffers;
 using Windows.Graphics.Capture;
 using Windows.UI.Core;

src/Uno.UWP/UI/Core/WeakEventHelper.cs

@@ -36,9 +36,9 @@ internal class WeakEventHelper
 		internal interface ITrimProvider
 		{
 			/// <summary>
-			/// Registers a callback to be called when GC triggerd
+			/// Registers a callback to be called when GC triggered
 			/// </summary>
-			/// <param name="callback">Function called with <paramref name="arrayPool"/> as the first parameter</param>
+			/// <param name="callback">Function called with <paramref name="target"/> as the first parameter</param>
 			/// <param name="target">instance to be provided when invoking <paramref name="callback"/></param>
 			void RegisterTrimCallback(Func<object, bool> callback, object target);
 		}