feat: extract CommunityToolkit version.

(cherry picked from commit 580e780e58)

demo/Semi.Avalonia.Demo.Desktop/Program.cs

@@ -16,13 +16,13 @@ class Program
     public static void Main(string[] args) => BuildAvaloniaApp()
         .With(new FontManagerOptions
         {
-            FontFallbacks = new[]
-            {
+            FontFallbacks =
+            [
                 new FontFallback
                 {
                     FontFamily = new FontFamily("Microsoft YaHei")
                 }
-            }
+            ]
         })
         .StartWithClassicDesktopLifetime(args);