* Set max_header_size to 38 per the upstream Neutron guide albeit the
header size can be variable:
https://tools.ietf.org/html/draft-ietf-nvo3-geneve-16#page-14
* The empty "plugs" entry results in the following error raised by the
auto-review tool of the snap store:
"invalid plugs entry (empty) lint-snap-v2_app_plugs (rabbitmq-plugins)"
Let's avoid this by removing the section altogether.
Change-Id: I1b192140c8ca3445bd817f7e583f303d1bb0a338