Alma: Return pickup location fields as strings.

Also adds a missing parameter.

module/VuFind/src/VuFind/ILS/Driver/Alma.php

@@ -1497,21 +1497,23 @@ class Alma extends AbstractBase implements \VuFindHttp\HttpServiceAwareInterface
      * This is responsible get a list of valid library locations for holds / recall
      * retrieval
      *
-     * @param array $patron Patron information returned by the patronLogin method.
+     * @param array $patron      Patron information returned by the patronLogin
+     * method.
+     * @param array $holdDetails Hold details
      *
      * @return array An array of associative arrays with locationID and
      * locationDisplay keys
      *
      * @SuppressWarnings(PHPMD.UnusedFormalParameter)
      */
-    public function getPickupLocations($patron)
+    public function getPickupLocations($patron, $holdDetails = null)
     {
         $xml = $this->makeRequest('/conf/libraries');
         $libraries = [];
         foreach ($xml as $library) {
             $libraries[] = [
-                'locationID' => $library->code,
-                'locationDisplay' => $library->name
+                'locationID' => (string)$library->code,
+                'locationDisplay' => (string)$library->name
             ];
         }
         return $libraries;