Fix old references to agent status builder

Fixes these tests:
* ion.services.sa.observatory.test.test_observatory_management_service_integration:TestObservatoryManagementServiceIntegration.test_observatory_extensions
* ion.services.sa.observatory.test.test_observatory_management_service_integration:TestObservatoryManagementServiceIntegration.test_observatory_org_extended 
* ion.services.sa.observatory.test.test_platform_launch:TestPlatformLaunch.test_platform_hierarchy_with_some_instruments