Add premium-series presence to Central US and East US regions

Author: AckoMSFT

articles/azure-sql/managed-instance/resource-limits.md

@@ -52,6 +52,8 @@ Support for the premium-series hardware generations (public preview) is currentl
 | Australia East | Yes | Yes | 
 | Canada Central | Yes | | 
 | Canada East | Yes | | 
+| Central US | Yes | | 
+| East US | Yes | | 
 | East US 2 | Yes | | 
 | France Central |  | Yes | 
 | Germany West Central |  | Yes |