Update default images for "tripleo launch heat"
Update default images for "tripleo launch heat"

Currently we have different defaults for `--heat-container-api-image`
and  `--heat-container-engine-image` in "openstack overcloud deploy"
vs "openstack tripleo launch heat" command.

Updating these defaults to be in sync with
"openstack overcloud deploy"[1]

[1] https://opendev.org/openstack/python-tripleoclient/src/branch/master/tripleoclient/v1/overcloud_deploy.py#L972-L990

Change-Id: Ibb8da41d9c916b794c148cbebe648b9c05c54a0a

openstack/python-tripleoclient