chore: use file-scoped namespace

src/Shared/HandyControl_Shared/Controls/Button/ContextMenuButton.cs

@@ -1,23 +1,22 @@
 using System.Windows.Controls;
 
 
-namespace HandyControl.Controls
-{
-    /// <summary>
-    ///     带上下文菜单的按钮
-    /// </summary>
-    public class ContextMenuButton : Button
-    {
-        public ContextMenu Menu { get; set; }
+namespace HandyControl.Controls;
 
-        protected override void OnClick()
+/// <summary>
+///     带上下文菜单的按钮
+/// </summary>
+public class ContextMenuButton : Button
+{
+    public ContextMenu Menu { get; set; }
+
+    protected override void OnClick()
+    {
+        base.OnClick();
+        if (Menu != null)
         {
-            base.OnClick();
-            if (Menu != null)
-            {
-                Menu.PlacementTarget = this;
-                Menu.IsOpen = true;
-            }
+            Menu.PlacementTarget = this;
+            Menu.IsOpen = true;
         }
     }
-}
+}