Add Slack channel for Project Antrea
Add Slack channel for Project Antrea

Antrea (https://github.com/vmware-tanzu/antrea) is an open-source CNI
plugin based on Open vSwitch. It was built specifically to be a
networking solution for Kubernetes clusters and supports Network
Policies.

We are adding a single channel at the moment (antrea) but may want to
have a dev channel in the future.

Signed-off-by: Antonin Bas <fb45519bfd86140bf21e06c2676c295f783a518b@vmware.com>

kubernetes/community,pwittrock/community,kubernetes/community,kubernetes/community,pwittrock/community