With a project structure like this:
* Executable project references a library project.
* The library project references a binding project (or assembly).
The binding project's assembly will be copied to the library project's
output directory during the build. Unless we also make sure any binding
resource packages are copied as well, the executable project won't find those,
and the final app won't contain any native bits from the binding project.
The solution is to add any binding resource packages to the list of
files to be copied to the library's output directory.
Fixes https://github.com/xamarin/xamarin-macios/issues/13910.
7ea0044224