Remove ParentControlHub, since control hubs will always be parents

Author: LandryNorris

packages/control-hub/src/ControlHub.ts

@@ -1,7 +1,3 @@
 import { ExpansionHub, ParentRevHub } from "@rev-robotics/expansion-hub";
 
-export interface ParentControlHub extends ParentRevHub, ControlHub {
-    readonly serialNumber: string;
-}
-
-export interface ControlHub extends ExpansionHub {}
+export interface ControlHub extends ExpansionHub, ParentRevHub {}