roleService -> loadRoleByIdentifier( $roleIdentifier ) fails with the exception Could not find 'Limitation' with identifier 'Group' if UserGroup limitation is used in role.

steps to reproduce

• create a role and include the policy content | read | group:self
• attempt to load the role by it's identifier in a command

        $repository = $this->getContainer()->get( 'ezpublish.api.repository' );
        $repository->setCurrentUser( $repository->getUserService()->loadUser( 14 ) );
        $roleService = $repository->getRoleService();
  
        if ( !$role = $roleService->loadRoleByIdentifier( $roleIdentifier ) )
        {
            $output->writeln( "Role $roleIdentifier not found" );
            exit;
        }
  

  The command will fail with

  [eZ\Publish\Core\Base\Exceptions\NotFoundException]
  Could not find 'Limitation' with identifier 'Group'

I believe the limitation is named UserGroup