add date facade alias (#5556)

config/app.php

@@ -201,6 +201,7 @@
         'Config' => Illuminate\Support\Facades\Config::class,
         'Cookie' => Illuminate\Support\Facades\Cookie::class,
         'Crypt' => Illuminate\Support\Facades\Crypt::class,
+        'Date' => Illuminate\Support\Facades\Date::class,
         'DB' => Illuminate\Support\Facades\DB::class,
         'Eloquent' => Illuminate\Database\Eloquent\Model::class,
         'Event' => Illuminate\Support\Facades\Event::class,