[PRQ#50040] Deletion Request for python-etcd3gw

MarsSeed [1] filed a deletion request for python-etcd3gw [2]: Cleanup of this unneeded server component package, whose only purpose on AUR was to build long abandoned and defunct Openstack server Python modules (see openstack-nova's deletion request, PRQ#50005, which is representative of the status of the other AUR/openstack-* packages). [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/python-etcd3gw/