public function downloadSummaryPerEmployee(Employee $employee)
 {
     $leaves = $employee->employee_leaves()->certified()->orderBy('start_date', 'desc')->get();
     if ($leaves->isEmpty()) {
         flash()->warning('Employee has no regular leave yet.');
         return redirect()->back();
     }
     write_form(new \DNSCHumanResource\FormWriters\WriteEmployeeRegularLeaveSummary($leaves));
 }