Rule source on GitHub

DowngradeContravariantArgumentTypeRector

Remove contravariant argument type declarations

 class ParentType {}
 class ChildType extends ParentType {}

 class A
 {
     public function contraVariantArguments(ChildType $type)
     {
     }
 }

 class B extends A
 {
-    public function contraVariantArguments(ParentType $type)
+    /**
+     * @param ParentType $type
+     */
+    public function contraVariantArguments($type)
     {
     }
 }

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\DowngradePhp74\Rector\ClassMethod\DowngradeContravariantArgumentTypeRector;

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