Changing the language of a window breaks displaying child nodes of a TreeView

まだ誰も着手していません。

### Bug explanation

Changing the language of a window breaks displaying child nodes of a TreeView. I assume it has something to do with an UI update because it breaks in another app when different TreeViews are displayed. The only way I can reliably reproduce the issue is with the language change.

Here is a video demonstrating the issue. I also uploaded an [example app](https://github.com/reiseder/material-design-tree-view-bug).

https://user-images.githubusercontent.com/31562861/229203111-cf8afc11-aac1-4830-878d-4d41ee21e4e9.mp4

Using Snoop I figured out that this [binding](https://github.com/MaterialDesignInXAML/MaterialDesignInXamlToolkit/blob/master/MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.TreeView.xaml#L359) breaks as it somehow references the wrong `ItemsHost` element.

I temporarily fixed the issue by changing the line from

```xml

```

to

```xml

```

I don't think that is the proper solution though.

### Version

4.6.1, 4.8.0

Start with MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.TreeView.xaml at the binding around line 359, then reproduce the problem using the linked example app and its language-change scenario. Investigate why the binding references the wrong ItemsHost after the UI update; done means TreeView child nodes display correctly after changing the window language.

索引モデルが issue の本文から書いたものです。