Only require image rpms if we are in a sle version older than sle15
Only require image rpms if we are in a sle version older than sle15

because sle15 will use the suse registry

Signed-off-by: Jordi Massaguer Pla <6858cec916b2a25e416959701ca32d40d47aefc7@suse.de>

ereslibre/caasp-container-manifests