Class "Spatie\Crawler\Crawler" not found

[bobclewell]

1. Install the package: composer require spatie/laravel-sitemap
2. Create a simple GenerateSitemap command per the docs to comb my app and create the sitemaps.

    public function handle()
    {
        SitemapGenerator::create(config('app.url'))
            ->writeToFile(public_path('sitemap.xml'));
    }

3. Run the command and get the error: Class "Spatie\Crawler\Crawler" not found

Why wouldn't this required dependency get installed with the package? Any ideas on a fix?