With the new TC resolution the community replaces Extended Maintenance
with Unmaintained status [1].
Since Murano project is marked as inactive as there were hardly any
maintenance, we move its old xena, wallaby and victoria branches to EOL
instead of moving them to Unmaintained. If anyone wants to resurrect
the project then the work should be started at the master branch
instead.
[1] https://governance.openstack.org/tc/resolutions/20230724-unmaintained-branches.html
Change-Id: I56f00a8b89c6c48620d0f61dc491038d3c10af60
cb916a58d8