doc: 移除扁平化数据源示例

Author: ArgoZhang

src/BootstrapBlazor.Server/Components/Samples/TreeViews.razor

@@ -211,7 +211,7 @@
     </div>
 </DemoBlock>
 
-<DemoBlock Title="@Localizer["TreeViewFlatTitle"]"
+@* <DemoBlock Title="@Localizer["TreeViewFlatTitle"]"
            Introduction="@Localizer["TreeViewFlatIntro"]"
            Name="FlatItems">
     <section ignore>
@@ -220,7 +220,7 @@
     <TreeView TItem="TreeFoo" Items="@FlatItems" ShowCheckbox="true"
                 AutoCheckChildren="true" AutoCheckParent="true"></TreeView>
 </DemoBlock>
-
+ *@
 <AttributeTable Items="@GetAttributes()"></AttributeTable>
 
 <AttributeTable Items="@GetTreeItemAttributes()" Title="@Localizer["TreeViewsAttribute"]"></AttributeTable>