* Include NetCoreAppCurrent configs in packages

The NetCoreAppCurrent configurations were omitted from packages to avoid
ever growing packages. Now that we adhere to the support policy for
packages we don't need to exclude them anymore as the policy defines a
baseline for .NETCoreApp configurations.

This will remove an artificial difference when source building the
repository and also make it so that partner repositories which don't
depend on a transport package like windowsdesktop (winforms) receive
the very latest assets that are included in the shared framework as
well.

* Fix package validation for non exposed inbox libs