refs #22022 [finc] adapt slot view helper in unit test

module/finc/tests/unit-tests/src/fincTest/RecordDriver/SolrBaseTestCase.php

@@ -144,7 +144,8 @@ class SolrBaseTestCase extends VuFindTestCase
             'serverUrl' => $serverUrl,
             'config' => $config,
             'url'   => $url,
-            'context' => new \VuFind\View\Helper\Root\Context()
+            'context' => new \VuFind\View\Helper\Root\Context(),
+            'slot' => new \VuFindTheme\View\Helper\Slot()
         ];
     }
 }