…rce that is an assembly ref (dotnet#112810)

When getting a resource where `ResourceResolve` handler returns an assembly with a manifest resource that is an assembly ref, we incorrectly resolved the reference on the original assembly instead of the assembly returned by the handler and then also looked for the resource on the original assembly again instead of using the referenced assembly.

This change includes a test for this case using IL. The manifest resource file (as opposed to assembly ref) case is already covered in libraries tests.