* Renamed `EnumerableObjectComparer` => `SequenceComparer` and added generic type param for items.
* Re-worked standard test support for generators to better match patterns/style of analyzer tests.
    - Removed need for Basic assembly package
    - Added `CachedSourceGeneratorTest<TGenerator, TVerifier>` to handle common cached validation.
* Added location retrieval extension for `AttributeData` to allow getting the location of the attribute itself for reporting diagnostic associated with the attribute.
* Reduced language runtime minimums to C# 12/.NET 8.0
* Renamed `SourceGeneratorTest<TSourceGenerator, TVerifier>` as `LanguageVerionsSourceGeneratorTest<TSourceGenerator, TVerifier>`
    - The new name better describes use, it is intended as a base class for some other type, particularly the new
`CachedSourceGeneratorTest<TGenerator, TVerifier>`
* Added extensions for C# `LanguageVersion` to get default runtime assemblies and nullability behavior etc.. based on language version.
* Converted all test extensions to use `IVerifier`
    - This makes the `Ubiquity.NET.SourceGenerator.Test.Utils` independent of the actual test framework so it should be more useful
    - Add MsTestVerifier to the UT itself so that there is an adapter that interacts with the MS Test framework of those libraries.
        - The `DefaultVerifier` implementation cheats and uses an `InvalidOperationException` for all cases and doesn't actually adapt to anything.

* Removed support for VB
   - Inclusion of VB support or any other language causes problems with [RS1038](https://github.com/dotnet/roslyn/blob/main/docs/roslyn-analyzers/rules/RS1038.md)
   - If per language support is really desired then the language specific support needs isolation to distinct libraries.
* Added `AttributeDataExtensions.GetLocation()` to get the location of an attribute.
* Renamed `x64.runsettings` to simply `.runsettings`
    - Apparently something changed in the IDE and it now requires that name.