UserTrait: set last access time

[AlexSkrypnyk]

  /**
   * @Then the last access time of user :name is :time
   */
  public function setUserLastAccess(string $name, string $time): void {
    /** @var \Drupal\user\UserInterface $user */
    $user = $this->userGetByName($name);
    $timestamp = (int) static::dateRelativeProcessValue($time, time());
    $user->setLastAccessTime($timestamp)->save();
  }