invoiceninja/app/Http/Controllers/ClientPortal/DashboardController.php

<?php
/**
 * Invoice Ninja (https://invoiceninja.com).
 *
 * @link https://github.com/invoiceninja/invoiceninja source repository
 *
 * @copyright Copyright (c) 2020. Invoice Ninja LLC (https://invoiceninja.com)
 *
 * @license https://opensource.org/licenses/AAL
 */

namespace App\Http\Controllers\ClientPortal;

use App\Http\Controllers\Controller;
use Illuminate\Contracts\View\Factory;
use Illuminate\View\View;

class DashboardController extends Controller
{
    /**
     * @return Factory|View
     */
    public function index()
    {
        return redirect()->route('client.invoices.index');
    }
}