Allow StateVarHash to YAML.load from runtime instantiate

Previously, we allowed it to be permitted in serialized columns, but this test
also requires it be permitted from miq_ae_workspace_runtime.rb instantiate.

spec/engine/miq_ae_state_machine_retry_spec.rb

@@ -183,7 +183,7 @@ def create_restart_model(script1, script2, script3)
   end
 
   it "check persistent hash" do
-    ActiveRecord::Base.yaml_column_permitted_classes << "MiqAeEngine::StateVarHash"
+    YamlPermittedClasses.app_yaml_permitted_classes |= [MiqAeEngine::StateVarHash]
     setup_model(method_script_state_var)
     expected = MiqAeEngine::StateVarHash.new('three' => 3, 'one' => 1, 'two' => 2, 'gravy' => 'train')
     send_ae_request_via_queue(@automate_args)