Inverted the impossible

Author: SimonDarksideJ

Assets/MixedRealityToolkit/_Core/Services/MixedRealityToolkit.cs

@@ -526,7 +526,7 @@ public bool RegisterService(Type type, IMixedRealityService service)
             }
             else
             {
-                if (typeof(IMixedRealityExtensionService).IsAssignableFrom(type))
+                if (!typeof(IMixedRealityExtensionService).IsAssignableFrom(type))
                 {
                     Debug.LogError($"Unable to register {service}. Concrete type does not implement the IMixedRealityExtensionService implementation.");
                     return false;