[Feature]: Add PHP 8.5 support

[JJCLane]

Feature summary

No response

Problem statement

There are a couple of calls to curl_close that are deprecated since PHP 8.5.

• https://github.com/Adyen/adyen-php-api-library/blob/v29.0.0/src/Adyen/HttpClient/CurlClient.php#L150
• https://github.com/Adyen/adyen-php-api-library/blob/v29.0.0/src/Adyen/HttpClient/CurlClient.php#L357

Proposed solution

Given that the library is still supporting >= PHP 7.3, I suggest the following solution:

if (PHP_VERSION_ID < 80000) {
    curl_close($ch);
}

Alternatives considered

No response

Additional context

No response