Resolved the compilation issue

Author: Shalini-Ashokan

src/Controls/tests/TestCases.iOS.Tests/snapshots/ios-26/Issue33783_SwitchThumbColor_DarkTheme.png

@@ -146,7 +146,7 @@ void UpdateTrackOffColor(UISwitch platformView)
 
 			void UpdateThumbColor(UISwitch platformView)
 			{
-				DispatchQueue.MainQueue.DispatchAsync(() =>
+				DispatchQueue.MainQueue.DispatchAsync(async () =>
 				{
 					if (VirtualView is null || PlatformView is null)
 						return;