Removed unused, meaningless code.

module/VuFind/src/VuFind/RecordDriver/SolrAuth.php

@@ -38,13 +38,6 @@ namespace VuFind\RecordDriver;
  */
 class SolrAuth extends SolrMarc
 {
-    /**
-     * Used for identifying database records
-     *
-     * @var string
-     */
-    protected $resourceSource = 'SolrAuth';
-
     /**
      * Get the short (pre-subtitle) title of the record.
      *