fix: Check records are actually related to an Operating Centre before…

… accesing that property. (#347)

app/api/module/Api/src/Entity/Licence/Licence.php

@@ -570,7 +570,7 @@ public function getGroupedConditionsUndertakings()
                     'notes' => $cu->getNotes(),
                     'createdOn' => $cu->getCreatedOn(true)
                 ];
-            } else {
+            } elseif ($cu->getOperatingCentre() !== null && $cu->getOperatingCentre()->getId() !== null) {
                 $ocConditionsUndertakings[$cu->getOperatingCentre()->getId()][$conditionType][] = [
                     'notes' => $cu->getNotes(),
                     'address' => [