Errors while fetching GitHub project info

[jlfranklin]

With release 8.4.0 of php-curl-class, attempts to fetch a project fail with the following (sanitized) errors:

Error: Class 'Curl\Url' not found in Curl\Curl->setUrl() (line 1178 of /path/to/docroot/libraries/php-curl-class/src/Curl/Curl.php).

and after the Url.php file is added via require_once:

PHP Fatal error:  Method Curl\\Url::__toString() must not throw an exception, caught Error: Class 'Curl\\StringUtil' not found in /path/to/docroot/libraries/php-curl-class/src/Curl/Curl.php on line 0\n

The library is assuming the use of the php autoloader.