PHP8 Curl returns CurlHandle (not resource)

Since PHP8 [`curl_init`](https://www.php.net/manual/en/function.curl-init.php) returns [`CurlHandle`](https://www.php.net/manual/en/class.curlhandle.php) (or false) instead of `resource|false`.

As the generated function has the wrong typing, PHPStan's is sad :'(