Extract the logic from MediaRouteChooserDialog

[MGaetan89]

Description

This PR extracts all the logic from MediaRouteChooserDialog into a dedicated ViewModel. This greatly simplifies the Compose code and eases testing of the logic.

Changes made

• Move logic from MediaRouteChooserDialog to MediaRouteChooserDialogViewModel.
• Create a TestMediaRouteProvider class to provide fake routes.
• Improve support on rotation so the state is not reset.
• Add tests to MediaRouteChooserDialogViewModel.
• Update Kover exclusion rules to ignore the Icons class, since it's a copy/paste from Compose Material.
• Update the "Release" badge in the README.md file to allow pre-releases:

Before	After

[github-actions]

Code Coverage

Overall Project	20.32% -8.44%	🟢
Files changed	52.59%	🟢

File	Coverage
MediaRouteChooserDialogViewModel.kt	94.12% -5.88%	🟢
MediaRouteButtonViewModel.kt	93.22%	🟢
MediaRouteChooserDialog.kt	0% -42.25%	🟢

[MGaetan89]

I've addressed the points we discussed this morning:

• The state is now preserved upon rotation.
• Changing the locale works as expected.