Adds server_certs_key_passphrase to octavia.conf
Adds server_certs_key_passphrase to octavia.conf

The server_certs_key_passphrase was added in
I06d329ca53bc36bd27f7870ae7c7ca0cf18575b2 and should be
a part of the example octavia.conf

Change-Id: I5e60e8fbb7af381b59c6d7b02d5ba8eb47e91720

openstack/octavia,openstack/octavia,openstack/octavia