refactor: 增加 OnClickTitleBarCallback 释放逻辑

Author: ArgoZhang

src/components/BootstrapBlazor.DockView/Components/DockViewComponent.razor.cs

@@ -200,6 +200,11 @@ protected override void Dispose(bool disposing)
     {
         base.Dispose(disposing);
 
+        if (OnClickTitleBarCallback != null)
+        {
+            OnClickTitleBarCallback = null;
+        }
+
         DockView.RemoveComponentState(Key);
     }
 }