Added string for anonymous user

classes/local/table/interaction_remaining_table.php

@@ -165,7 +165,7 @@ class interaction_remaining_table extends interaction_table {
         // Otherwise, show latest action commited by user.
         global $CFG;
         if ($row->userid == -1) {
-            $userlink = get_string("anonymous_user");
+            $userlink = get_string("anonymous_user", 'tool_lifecycle');
         } else {
             $userlink = \html_writer::link($CFG->wwwroot . '/user/profile.php?id=' . $row->userid, fullname($row));
         }

lang/en/tool_lifecycle.php

@@ -163,6 +163,7 @@ $string['manual_trigger_process_existed'] = 'A workflow for this course already
 
 $string['coursename'] = 'Course name';
 $string['lastaction'] = 'Last action on';
+$string['anonymous_user'] = 'Anonymous User';
 
 $string['workflow_started'] = 'Workflow started.';
 $string['workflow_is_running'] = 'Workflow is running.';