Comptroller General of the United States shall submit to Congress a report on— (i) pharmacy networks that have contracted with group health plans, health insurance issuers offering group health insurance coverage, or entities providing pharmacy benefits management services on behalf of such plans or issuers, including networks with pharmacies that are under common ownership (in whole or part) with such plans, issuers, or entities (including entities that provide pharmacy benefits administrative services on behalf of such plans or issuers)