set config variables for env variables

database/seeders/DatabaseSeeder.php

@@ -8,7 +8,7 @@ class DatabaseSeeder extends Seeder
 {
     public function run()
     {
-        if (env('DEV') == 1) {
+        if (config('dev') == 1) {
             $this->call(DevSeeder::class);
         } else {
             $this->call(ProdSeeder::class);