MDL-80917 core_backup: Clear restored course cache

lib/classes/task/asynchronous_copy_task.php

@@ -26,6 +26,7 @@
 namespace core\task;
 
 use async_helper;
+use cache_helper;
 
 defined('MOODLE_INTERNAL') || die();
 
@@ -207,6 +208,9 @@ class asynchronous_copy_task extends adhoc_task {
             fulldelete($backupbasepath);
         }
 
+        rebuild_course_cache($restorerecord->itemid, true);
+        cache_helper::purge_by_event('changesincourse');
+
         $duration = time() - $started;
         mtrace('Course copy: Copy completed in: ' . $duration . ' seconds');
     }