Microsoft Graph Service: Retiring TLS 1.0 and 1.1 and preparing for TLS 1.2 in US Gov Cloud

Update your Microsoft Graph clients in US Gov Cloud (https://graph.microsoft.us & https://dod-graph.microsoft.us) to TLS 1.2 by 8/5/2020 to ensure that you maintain uninterrupted access to Microsoft Graph Service.
Source: Azure Roadmap