Revert "doc: correct down time date"
Revert "doc: correct down time date"

This reverts commit 92184ab0f646d31583f0486934c969c964e86f47.

chk1/openmensa,openmensa/openmensa,chk1/openmensa,openmensa/openmensa,openmensa/openmensa,openmensa/openmensa