Add resw support for language qualifiers

[jeromelaban]

Uno default project use different folder to place different language resw file.

But latest visualstudio updated its resource explorer . it is better to use filename rather folder.

For new resource explorer, different resw file in different folders is reagrded as different resource

But if they are in same folder, it will be same resource.

Originally posted by @DJDQfff in #18801

[jeromelaban]

Note to contributors

The implementation should be located here:

uno/src/SourceGenerators/Uno.UI.Tasks/ResourcesGenerator/ResourcesGenerationTask.cs

Line 75 in ce498ef

var resourceCandidate = ResourceCandidate.Parse(resource.ItemSpec, resource.ItemSpec);

and

uno/src/Uno.UWP/ApplicationModel/Resources/Core/ResourceCandidate.cs

Lines 32 to 44 in ce498ef

	internal static ResourceCandidate Parse(string fullPath, string relativePath)
	{
	var logicalPath = GetLogicalPath(relativePath);
	var qualifiers = relativePath
	.Split(Path.DirectorySeparatorChar, '_', '.')
	.Select(ResourceQualifier.Parse)
	.Reverse()
	.Where(p => p != null)
	.ToArray();
	return new ResourceCandidate(qualifiers, fullPath, logicalPath);
	}