Revert "ci: disable Collabora's LAVA lab for maintance"
After the merge request !21355 (merged), and when the farm gets back on line, this is prepared to re-enable the farm in the mesa CI.
Do not push before confirmation that Collabora LAVA farm is up again.
Upgrade is expected to occur until 2023-03-06 12:00 GMT
(1 PM CET).