aufn-ceph: Drop cephadm_image override

The default in the base config should use this when Ceph images are not synced to Pulp.

Author: markgoddard

etc/kayobe/environments/aufn-ceph/cephadm.yml

@@ -2,9 +2,6 @@
 ###############################################################################
 # Cephadm deployment configuration.
 
-# Ceph container image.
-cephadm_image: "quay.io/ceph/ceph:v16.2.5"
-
 # List of additional cephadm commands to run before deployment
 # cephadm_commands:
 #   - "config set global osd_pool_default_size {{ [3, groups['osds'] | length] | min }}"