Persona verification in Badges, incorrect audience parameter when port is specified

When connecting to Mozilla Backpack in /badges/backpackconnect.php, the assertion is verified using Mozilla Persona. However, if the port is specified in $CFG->wwwroot, the audience parameter is incorrect, because it is missing a colon.

// Line 50

$wwwparts = parse_url($CFG->wwwroot);

$audience = $wwwparts['scheme'] . '://' . $wwwparts['host'];

$audience .= isset($wwwparts['port']) ? $wwwparts['port'] : '';

If $CFG->wwwroot is, for example, https://www.example.com:443, the $audience variable will be incorrectly https://www.example.com443. A simple fix:

$audience .= isset($wwwparts['port']) ? ':' . $wwwparts['port'] : '';