Fix for Accent Color Change Theme bug

[raghavdhingra24]

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Hi there,
Accent color change in QT>=6.5 makes windows title bar go back to light mode and no method is currently available to prevent this - See: https://www.qt.io/blog/dark-mode-on-windows-11-with-qt-6.5. This code is currently hacky and sometimes fails to work or cause a flicker.

Video:

Before	After
https://github.com/marticliment/WingetUI/assets/106472154/2ff63f61-b449-497a-ac45-7a9d59bce2c9	https://github.com/marticliment/WingetUI/assets/106472154/eec61ccc-ad3a-465e-b510-78c3e4634a5f
	Updated Video: https://github.com/marticliment/WingetUI/assets/106472154/13621319-1909-406b-893a-3940562d6ec0

Some other ways to reduce currently occurring problems -

1. We can increase the timeout to 2000ms or 3000ms for waiting for qt to finish changing the theme - decreases failure but causes the app show light mode for longer time.
2. Set app style to None - can have some unwanted behavior.

Thanks

Edit: Formatting
Edit2: Added updated video

[raghavdhingra24]

I have updated timer to wait for 3000ms. This makes the theme change back to selected one work most of the times.

Updated Video -
https://github.com/marticliment/WingetUI/assets/106472154/13621319-1909-406b-893a-3940562d6ec0

[marticliment]

Seems fine until this bug gets fixed by Qt.
When ready let me know to be able to merge.

Thanks!

[raghavdhingra24]

Checked on Windows 10 and the code is working correctly, ready to merge.

[marticliment]

I have done my testing and it appears to work fine.

Thank you!