Move Microsoft.Maui.Graphics.GDI.Winforms into the Maui repo

This was initially excluded from the merge in #8147 because it was not actually building in that repo.

Based on demand this can be moved here. However, in order to make sure that the code in the repo is actually buildable, we are not moving it right away.

The issue names Microsoft.Maui.Graphics.GDI.Winforms and references its exclusion from merge #8147, but provides no source files or tests. Start by locating the component and determining why it does not build in the target repository; done means it is moved into dotnet/maui and the code builds there.

Written by the indexing model from the issue text.