fix: 🐛 fix not checking for key existence in aups

* bug caused passing null as argument to json_decode(...) function when
the voShortName or aup key has not been found in the defined AUPs
(defined for vo or in entityless attribute)

Author: Dominik Frantisek Bucik

lib/Auth/Process/ForceAup.php

@@ -266,6 +266,10 @@ private function fillAupsToBeApproved($requestedAups, $aups, $userApprovedAups)
     {
         $aupsToBeApproved = [];
         foreach ($requestedAups as $requestedAup) {
+            $aupsInJson = $aups[$requestedAup];
+            if (empty($aupsInJson)) {
+                continue;
+            }
             $decodedAups = json_decode($aups[$requestedAup]);
             $latestAup = $this->getLatestAup($decodedAups);