code: protected function prepareHeader(array $data)
      {
          return array_merge_recursive(
              [
                  'date' => trans('dashboard::logs.date'),
                  'all'  => trans('dashboard::logs.all'),
              ],
              $this->levels->names($this->locale)
          );
      }
docs: Prepare table header.
  
  @param array $data
  
  @return array