Add add-ons' credentials to known credentials list
Add add-ons' credentials to known credentials list

We ask the user to provide these via `chef-server-ctl set-secret GROUP
NAME`, and that command only accepts known combinations. Adding the
add-ons' secrets to this list.

Signed-off-by: Stephan Renatus <3d1a7d0a294b6d8e799ad6e122143905f17f9530@chef.io>

itmustbejj/chef-server,juliandunn/chef-server-1,itmustbejj/chef-server,chef/chef-server,itmustbejj/chef-server,chef/chef-server,juliandunn/chef-server-1,itmustbejj/chef-server,juliandunn/chef-server-1,itmustbejj/chef-server,chef/chef-server,chef/chef-server,juliandunn/chef-server-1,chef/chef-server,juliandunn/chef-server-1,chef/chef-server