Deprecated ColorValue and DynamicColor

[mischreiber]

Platforms Impacted

• iOS
• macOS

Description of changes

As a follow-up to #1914, let's deprecate the ColorValue and DynamicColor objects, since they aren't used/needed by the new FluentTheme APIs.

Also added some new unit tests to augment the now deprecated ones around ColorValue and DynamicColor.

Binary change

Total increase: 8 bytes
Total decrease: -8,344 bytes

File	Before	After	Delta
Total	30,912,584 bytes	30,904,248 bytes	🎉 -8,336 bytes

Full breakdown

File	Before	After	Delta
DynamicColor.o	49,280 bytes	49,288 bytes	⚠️ 8 bytes
__.SYMDEF	4,823,000 bytes	4,822,976 bytes	🎉 -24 bytes
UIColor+Extensions.o	81,576 bytes	73,256 bytes	🎉 -8,320 bytes

Verification

Built and tested -- no real code changes are made, so no behavior changes to verify.

Pull request checklist

This PR has considered:

• Light and Dark appearances
• iOS supported versions (all major versions greater than or equal current target deployment version)
• VoiceOver and Keyboard Accessibility
• Internationalization and Right to Left layouts
• Different resolutions (1x, 2x, 3x)
• Size classes and window sizes (iPhone vs iPad, notched devices, multitasking, different window sizes, etc)
• iPad Pointer interaction
• SwiftUI consumption (validation or new demo scenarios needed)
• Objective-C exposure (provide it only if needed)

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