ISTWCMS-4882: Use WebformInterface::CONFIRMATION_INLINE

Correction of 7ebc8ddd.

uw_cfg_common.module

@@ -380,7 +380,7 @@ function uw_cfg_common_webform_create(WebformInterface $webform) {
 
   // On admin/structure/webform/manage/FORM/settings/confirmation, default
   // "Confirmation type" to "inline".
-  $webform->setSetting('confirmation_type', 'inline');
+  $webform->setSetting('confirmation_type', WebformInterface::CONFIRMATION_INLINE);
 
   // Set so that uw_cfg_common_webform_build_access_denied_alter() will run.
   // This value is tested for in Webform::preRenderWebformElement().