SA-CORE-2020-011 followup by xjm: Clean up coding standards in test.

namespace Drupal\Tests\file\Functional;

use Drupal\Core\Entity\Plugin\Validation\Constraint\ReferenceAccessConstraint;

use Drupal\Component\Render\FormattableMarkup;

use Drupal\file\Entity\File;

use Drupal\node\Entity\NodeType;

use Drupal\user\RoleInterface;