Update legacy_plugins.md to include HBM authz plugin
Update legacy_plugins.md to include HBM authz plugin

Signed-off-by: Julien Kassar <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@kassisol.com>

allencloud/cli,thaJeztah/cli,Zebrilee/cli,dnephin/cli,e11137/cli,docker/cli,riyazdf/cli,redpanda/cli,riyazdf/cli,cpuguy83/cli,allencloud/cli,Zebrilee/cli,docker/cli,redpanda/cli,ashfall/cli,ashfall/cli,thaJeztah/cli,cpuguy83/cli,dnephin/cli,e11137/cli