3.12.0 has been released, and the gluster roadmap on the site has been updated to EOL 3.11 and 3.8, as a result the gerrit dashboards for the same can be removed from the list of dashboards that are maintained at the project level.
Removed the old dashbaords. I've also taken the liberty of removing the NetBSD conditions from all the dashboards, since it's no longer a blocking flag.