[CLEANUP] Remove superfluous Rector rule

Since #1201, this becomes a duplicate.

Author: JakeQZ

config/rector.php

@@ -35,7 +35,4 @@
         PHPUnitSetList::PHPUNIT_80,
         // PHPUnitSetList::PHPUNIT_CODE_QUALITY,
     ])
-    ->withRules([
-        AddVoidReturnTypeWhereNoReturnRector::class,
-    ])
     ->withImportNames(true, true, false);