[CI] use memmos instead of eur0c

One hard disk drive is dead in our "eur0c" server. The RAID array needs
it to be replaced. eur0c is 2 months out of warranty. We already had this
budgetized, but Marchés Publics says we can only buy from one supplier,
and this supplier has 21 days delivery delays for this HDD.

Let's use another server instead.