[WPF] Symbol icons appear as empty boxes after creating a new solution with Navigation Pane and MVVM Toolkit

[JKamsker]

Describe the bug

When creating a new solution with Template Studio using the Navigation Pane and MVVM Toolkit, the expected symbol icons are not displayed correctly. Instead, they appear as empty boxes.

To Reproduce

1. Open Template Studio in your development environment.
2. Start a new solution with Template Studio.
3. Select 'Navigation Pane' as the project type.
4. Choose 'MVVM Toolkit' as the design pattern.
5. Add some pages to the project.
6. Click 'Create' to generate the project.

Additional context

Expected Behavior

The symbol icons for the added pages should be displayed correctly in the navigation pane.

Actual Behavior

The symbol icons are showing up as empty boxes.

Applies to the following platforms:

• WinUI
• WPF
• UWP

About your setup

• Visual Studio Version: 17.8.0
• Template Studio Wizard Version: 5.3
• Windows Version Win 10 22H2
• Windows Build: 19045.3693