corrected namespace in event class

src/Event/SolrDocumentAlterSubscriber.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\my_module;
+namespace Drupal\roblib_alter_solr;
 
 use Drupal\search_api\IndexInterface;
 use Drupal\search_api\Item\ItemInterface;