Resolver does not correctly discard export when module imports the same package

If a module both imports and exports the same package, this means the resolver has a choice to honor either the export or the import of the package. In the case where the resolve decides to honor the import, then the module's export for that same package is effectively discarded. Unfortunately, the resolver was not actually discarding the export in this case, so it is possible that another module might be wired to the effectively discarded export, even though the exporting module is importing the package from another provider. This results in some form of a re-export of the package, which is not spec compliant. We need to modify the resolver to check for this case.