MDL-48795 lang: Update message for nothingnew

In lang/en/moodle.php file

lang/en/moodle.php

@@ -1327,7 +1327,7 @@
 $string['notenrolledprofile'] = 'This profile is not available because this user is not enrolled in this course.';
 $string['noteusercannotrolldatesoncontext'] = '<strong>Note:</strong> The ability to roll dates when restoring this backup has been disabled because you lack the required permissions.';
 $string['noteuserschangednonetocourse'] = '<strong>Note:</strong> Course users need to be restored when restoring user data (in activities, files or messages). This setting has been changed for you.';
-$string['nothingnew'] = 'Nothing new since your last login';
+$string['nothingnew'] = 'No recent activity';
 $string['nothingtodisplay'] = 'Nothing to display';
 $string['notice'] = 'Notice';
 $string['noticenewerbackup'] = 'This backup file has been created with Moodle {$a->backuprelease} ({$a->backupversion}) and it\'s newer than your currently installed Moodle {$a->serverrelease} ({$a->serverversion}). This could cause some inconsistencies because backwards compatibility of backup files cannot be guaranteed.';