PHP 8.5 deprecation notice

`curl_close()` is deprecated in PHP 8.5, which means that calling this function will throw a notice. 

According to the PHP documentation, this function does nothing since PHP 8.0. I see that other packages that aim to support PHP versions prior to 8.0 use something like the below, which should avoid causing the notice:

```
if (PHP_VERSION_ID < 80000) {
            curl_close($resource);
}
```
