Migrate Compatibility.Core platform-specific unit tests to device tests

[jfversluis]

There are unit tests under:

• src\Compatibility\Core\tests\Android
• src\Compatibility\Core\tests\iOS
• src\Compatibility\Core\tests\WinUI

That are not running right now. Probably those have been copied over from Xamarin.Forms where they could run as unit tests, but now with .NET MAUI this is not possible. The way to still make these run is by turning them into device tests, probably either under src\Controls\tests\DeviceTests or src\Core\tests\DeviceTests.

As much as possible, try to see if there is already an existing test-case in the existing device tests. If yes, the compatibility test can be ignored. If not, convert the compatibility test to a device test.

Tests that reference obsoleted controls (like Frame) do not need to be converted.