Command does not execute after CanExecute is false than true

### Describe the bug

Command binding for checkbox stops working for unknown reason.

### Regression

_No response_

### Steps to reproduce

```text
clone https://github.com/leaderanalytics/LeaderPivot.XAML.WPF.git

set branch to `require_one_measure`

Usage note: Measures are checkboxes in upper left. Grand Totals is not a measure. See screenshot below.

Uncheck than re-check arbitrary measures to verify command handler executes.

Uncheck all measures except last (which will be disabled) as shown in screenshots area below.

Re-check any measure. The command does not execute even though it is enabled. It appears that after CanExecute returns false than true the command does not execute normally.
```

### Expected behavior

Command executes if CanExecute returns true.

### Screenshots

Uncheck all measures except last (which will be disabled):

### IDE and version

VS 2022

### IDE version

_No response_

### Nuget packages

- [ ] CommunityToolkit.Common
- [ ] CommunityToolkit.Diagnostics
- [ ] CommunityToolkit.HighPerformance
- [ ] CommunityToolkit.Mvvm (aka MVVM Toolkit)

### Nuget package version(s)

8.0.0-preview4

### Additional context

_No response_

### Help us help you

No, just wanted to report this