[neutron][release] Proposing transition to EOL Train (all Neutron related projects)

Hello:

I'm sending this mail in advance to propose transitioning Neutron and all related projects to EOL. I'll propose this topic too during the next Neutron meeting.

The announcement is the first step [1] to transition a stable branch to EOL.

The patch to mark these branches as EOL will be pushed in two weeks. If you have any inconvenience, please let me know in this mail chain or in IRC (ralonsoh, #openstack-neutron channel). You can also contact any Neutron core reviewer in the IRC channel.

Regards.

[1] https://docs.openstack.org/project-team-guide/stable-branches.html#end-of-li...