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FileDefaultSchemeRector

Fixes deprecated file_default_scheme calls

-$file_default_scheme = file_default_scheme();
+$file_default_scheme = \Drupal::config('system.file')->get('default_scheme');

Configure your rector.php:

<?php

use DrupalRector\Drupal8\Rector\Deprecation\FileDefaultSchemeRector;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withRules([
        FileDefaultSchemeRector::class,
    ]);