[[MediaWiki:Group-oversight-member/pt-br]]

There is a chance that this message is local to the Portuguese Wikipedia only. it could be a leftover from older such page names that have been renamed or moved, but I did not investigate. You can either edit it in the Wikipedia, or request its deletion there, or leave it as it is. Which option is your best choice depends. If you want to follow the issue, find out what use the Wikipedia makes of it, if any at all.