[ProgressBar] Colors do not change according to theme

[teresathompson]

Describe the bug

This bug occurs when the user toggles between themes, such as light and dark modes, but the progress bar fails to update its colors properly based on the active theme.

Steps to reproduce the bug

1. Open WinUI 3 Gallery and navigate to ProgressBar.
2. When the control opens for the first time in the selected theme, the colors are correct for the theme selected.
3. If you change the theme, the color of the progress bar remains the same, and doesn't adapt to the new theme selected.
4. Furthermore, if you toggle between themes several times, the indeterminate progress bar (running state) will run the animation in the color for light mode, then in the color for dark mode.

Expected behavior

The expected behavior for this control is to change the color according to the theme.

Screenshots

NuGet package version

WinUI 3 - Windows App SDK 1.4.0: 1.4.230822000

Windows version

Windows 11 (22H2): Build 22621

Additional context

No response