[BUG] ProgressBarAnimationBehavior set Easing in XAML (Windows)

### Is there an existing issue for this?

- [x] I have searched the existing issues

### Did you read the "Reporting a bug" section on Contributing file?

- [x] I have read the "Reporting a bug" section on Contributing file: https://github.com/CommunityToolkit/Maui/blob/main/CONTRIBUTING.md#reporting-a-bug

### Current Behavior

Using the `Easing` property directly in `XAML` in `ProgressBarAnimationBehaviorPage.xaml` file result in a
`Value cannot be null.
Parameter name: type` error after building the `CommunityToolkit.Maui.Sample` project.
_I only tested on Windows Machine / Debug since it is my usual starting point before even trying to android emulator (that make my PC very slow)_

**EDIT NOTE** : I see this is maybe known, due to the fact there is this comment in the code behind `ProgressBarAnimationBehaviorPage.xaml.cs` :

> // Work-around for Error XFC0009 when assigning Easing in XAML
> // No property, BindableProperty, or event found for "Easing", or mismatching type between value and property. (XFC0009)

Not the same error, but seems to be the same cause. May be at least point this out clearly in the docs ?

### Expected Behavior

Either fix this error to allow specify the easing property directly in `XAML`, or remove this property exposure from `XAML`

### Steps To Reproduce

1. Copy Community Toolkit Sample project (or clone repo)
2. Under Sample -> CommunityToolkit.Maui.Sample project -> Pages -> Behaviors -> ProgressBarAnimationBehaviorPage.xaml file modify :
```xml





```

into

```xml





```

### Link to public reproduction project repository

https://github.com/CommunityToolkit/Maui/tree/main/samples

### Environment

```markdown
- .NET MAUI CommunityToolkit: 11.2.0 (just did a git pull before testing)
- OS:windows10.0.19041.0
- .NET MAUI: 9.0.60
```

### Anything else?

_No response_