src/Fixer/Phpdoc/PhpdocNoEmptyReturnFixer.php
private function fixAnnotation(DocBlock $doc, Annotation $annotation)
    {
        $types = $annotation->getNormalizedTypes();

        if (1 === \count($types) && ('null' === $types[0] || 'void' === $types[0])) {
            $annotation->remove();
        }
    }
private function fixAnnotation(DocBlock $doc, Annotation $annotation)
    {
        $types = $annotation->getNormalizedTypes();

        if (1 === \count($types) && ('null' === $types[0] || 'void' === $types[0])) {
            $annotation->remove();
        }
    }
Remove return void or return null annotations..

@param DocBlock   $doc
@param Annotation $annotation