Declare who can send what mailman3 fedmsg stuff.

inventory/group_vars/mailman

@@ -18,6 +18,8 @@ fedmsg_certs:
 - service: mailman
   owner: mailman
   group: mailman
+  can_send:
+  - mailman.receive
 
 # Postfix main.cf
 postfix_group: mailman

inventory/group_vars/mailman-stg

@@ -17,6 +17,8 @@ fedmsg_certs:
 - service: mailman
   owner: mailman
   group: mailman
+  can_send:
+  - mailman.receive
 
 # default virt install command is for a single nic-device
 # define in another group file for more nics (see buildvm)