CommunityToolkit.WinUI.UI.FrameworkElementExtensions.FindChild throw System.InvalidCastException with CollectionView

### Describe the bug

CommunityToolkit.WinUI.UI.FrameworkElementExtensions.FindChild throw System.InvalidCastException when a view contains CollectionView

### Steps to reproduce

```text
create a view with ListView
create CollectionView with CollectionView.Source = IEnumerable where T is interface;
ListView.ItemsSource bind to CollectionView.View
try to find any FrameworkElement on the view
```

### Expected behavior

FindChild must return found element or null if view doesn't contain it.

### Screenshots

_No response_

### Code Platform

- [ ] UWP
- [X] WinAppSDK / WinUI 3
- [ ] Web Assembly (WASM)
- [ ] Android
- [ ] iOS
- [ ] MacOS
- [ ] Linux / GTK

### Windows Build Number

- [X] Windows 10 1809 (Build 17763)
- [X] Windows 10 1903 (Build 18362)
- [X] Windows 10 1909 (Build 18363)
- [X] Windows 10 2004 (Build 19041)
- [X] Windows 10 20H2 (Build 19042)
- [X] Windows 10 21H1 (Build 19043)
- [X] Windows 10 21H2 (Build 19044)
- [X] Windows 10 22H2 (Build 19045)
- [X] Windows 11 21H2 (Build 22000)
- [ ] Other (specify)

### Other Windows Build number

_No response_

### App minimum and target SDK version

- [ ] Windows 10, version 1809 (Build 17763)
- [ ] Windows 10, version 1903 (Build 18362)
- [ ] Windows 10, version 1909 (Build 18363)
- [ ] Windows 10, version 2004 (Build 19041)
- [ ] Windows 10, version 2104 (Build 20348)
- [X] Windows 11, version 22H2 (Build 22000)
- [ ] Other (specify)

### Other SDK version

_No response_

### Visual Studio Version

_No response_

### Visual Studio Build Number

_No response_

### Device form factor

_No response_

### Additional context

Test example
[CollectionViewTest](https://github.com/megamechanic/WinUIBugs)

### Help us help you

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### Tasks
```

Commencez par CommunityToolkit.WinUI.UI.FrameworkElementExtensions.FindChild et reproduisez l’échec à l’aide de l’exemple CollectionViewTest lié. Testez un ListView lié à une CollectionView dont la source est IEnumerable avec un type d’élément d’interface. C’est terminé lorsque FindChild renvoie le FrameworkElement correspondant, ou null lorsqu’il est absent, sans lever d’InvalidCastException.

Rédigé par le modèle d'indexation à partir du texte de l'issue.