Use Str class instead of helper function

config/database.php

@@ -1,5 +1,7 @@
 <?php
 
+use Illuminate\Support\Str;
+
 return [
 
     /*
@@ -117,7 +119,7 @@
 
         'options' => [
             'cluster' => env('REDIS_CLUSTER', 'predis'),
-            'prefix' => str_slug(env('APP_NAME', 'laravel'), '_').'_database',
+            'prefix' => Str::slug(env('APP_NAME', 'laravel'), '_').'_database',
         ],
 
         'default' => [