More precisions:
I'm using the tripleo-operator-ansible, and this is the full error:

Buildah failed with the following error: The following jobs were incomplete: [{'base': ['collectd', 'cron', 'etcd', 'haproxy', 'keepalived', 'mariadb', 'memcached', 'multipathd', {'os': [{'aodh-base': ['aodh-api', 'aodh-evaluator', 'aodh-listener', 'aodh-notifier']}, {'barbican-base': ['barbican-api', 'barbican-keystone-listener', 'barbican-worker']}, {'ceilometer-base': ['ceilometer-central', 'ceilometer-compute', 'ceilometer-ipmi', 'ceilometer-notification']}, {'cinder-base': ['cinder-api', 'cinder-backup', 'cinder-scheduler', 'cinder-volume']}, {'designate-base': ['designate-api', 'designate-backend-bind9', 'designate-central', 'designate-mdns', 'designate-producer', 'designate-sink', 'designate-worker']}, 'glance-api', {'gnocchi-base': ['gnocchi-api', 'gnocchi-metricd', 'gnocchi-statsd']}, {'heat-base': ['heat-all', 'heat-api', 'heat-api-cfn', 'heat-engine']}, 'horizon', {'ironic-base': ['ironic-api', 'ironic-conductor', 'ironic-inspector', 'ironic-pxe']}, 'iscsid', 'keystone', {'manila-base': ['manila-api', 'manila-scheduler', 'manila-share']}, {'mistral-base': ['mistral-api', 'mistral-engine', 'mistral-event-engine', 'mistral-executor']}, {'neutron-base': ['ironic-neutron-agent', {'neutron-agent-base': ['neutron-dhcp-agent', 'neutron-l3-agent', 'neutron-metadata-agent-ovn']}, 'neutron-metadata-agent', 'neutron-openvswitch-agent', 'neutron-server', 'neutron-server-ovn', 'neutron-sriov-agent']}, {'nova-base': ['nova-api', 'nova-compute', 'nova-compute-ironic', 'nova-conductor', 'nova-libvirt', 'nova-novncproxy', 'nova-scheduler']}, {'novajoin-base': ['novajoin-notifier', 'novajoin-server']}, {'octavia-base': ['octavia-api', 'octavia-health-manager', 'octavia-housekeeping', 'octavia-worker']}, 'placement-api', {'swift-base': ['swift-account', 'swift-container', 'swift-object', 'swift-proxy-server']}, 'tempest', 'zaqar-wsgi']}, {'ovn-base': ['ovn-controller', 'ovn-nb-db-server', 'ovn-northd', 'ovn-sb-db-server']}, 'qdrouterd', 'rabbitmq', 'redis', 'rsyslog', 'tripleoclient']}]                                                                                                                    
{'base': ['collectd', 'cron', 'etcd', 'haproxy', 'keepalived', 'mariadb', 'memcached', 'multipathd', {'os': [{'aodh-base': ['aodh-api', 'aodh-evaluator', 'aodh-listener', 'aodh-notifier']}, {'barbican-base': ['barbican-api', 'barbican-keystone-listener', 'barbican-worker']}, {'ceilometer-base': ['ceilometer-central', 'ceilometer-compute', 'ceilometer-ipmi', 'ceilometer-notification']}, {'cinder-base': ['cinder-api', 'cinder-backup', 'cinder-scheduler', 'cinder-volume']}, {'designate-base': ['designate-api', 'designate-backend-bind9', 'designate-central', 'designate-mdns', 'designate-producer', 'designate-sink', 'designate-worker']}, 'glance-api', {'gnocchi-base': ['gnocchi-api', 'gnocchi-metricd', 'gnocchi-statsd']}, {'heat-base': ['heat-all', 'heat-api', 'heat-api-cfn', 'heat-engine']}, 'horizon', {'ironic-base': ['ironic-api', 'ironic-conductor', 'ironic-inspector', 'ironic-pxe']}, 'iscsid', 'keystone', {'manila-base': ['manila-api', 'manila-scheduler', 'manila-share']}, {'mistral-base': ['mistral-api', 'mistral-engine', 'mistral-event-engine', 'mistral-executor']}, {'neutron-base': ['ironic-neutron-agent', {'neutron-agent-base': ['neutron-dhcp-agent', 'neutron-l3-agent', 'neutron-metadata-agent-ovn']}, 'neutron-metadata-agent', 'neutron-openvswitch-agent', 'neutron-server', 'neutron-server-ovn', 'neutron-sriov-agent']}, {'nova-base': ['nova-api', 'nova-compute', 'nova-compute-ironic', 'nova-conductor', 'nova-libvirt', 'nova-novncproxy', 'nova-scheduler']}, {'novajoin-base': ['novajoin-notifier', 'novajoin-server']}, {'octavia-base': ['octavia-api', 'octavia-health-manager', 'octavia-housekeeping', 'octavia-worker']}, 'placement-api', {'swift-base': ['swift-account', 'swift-container', 'swift-object', 'swift-proxy-server']}, 'tempest', 'zaqar-wsgi']}, {'ovn-base': ['ovn-controller', 'ovn-nb-db-server', 'ovn-northd', 'ovn-sb-db-server']}, 'qdrouterd', 'rabbitmq', 'redis', 'rsyslog', 'tripleoclient']} raised the following exception: The following jobs were incomplete: [{'os': [{'aodh-base': ['aodh-api', 'aodh-evaluator', 'aodh-listener', 'aodh-notifier']}, {'barbican-base': ['barbican-api', 'barbican-keystone-listener', 'barbican-worker']}, {'ceilometer-base': ['ceilometer-central', 'ceilometer-compute', 'ceilometer-ipmi', 'ceilometer-notification']}, {'cinder-base': ['cinder-api', 'cinder-backup', 'cinder-scheduler', 'cinder-volume']}, {'designate-base': ['designate-api', 'designate-backend-bind9', 'designate-central', 'designate-mdns', 'designate-producer', 'designate-sink', 'designate-worker']}, 'glance-api', {'gnocchi-base': ['gnocchi-api', 'gnocchi-metricd', 'gnocchi-statsd']}, {'heat-base': ['heat-all', 'heat-api', 'heat-api-cfn', 'heat-engine']}, 'horizon', {'ironic-base': ['ironic-api', 'ironic-conductor', 'ironic-inspector', 'ironic-pxe']}, 'iscsid', 'keystone', {'manila-base': ['manila-api', 'manila-scheduler', 'manila-share']}, {'mistral-base': ['mistral-api', 'mistral-engine', 'mistral-event-engine', 'mistral-executor']}, {'neutron-base': ['ironic-neutron-agent', {'neutron-agent-base': ['neutron-dhcp-agent', 'neutron-l3-agent', 'neutron-metadata-agent-ovn']}, 'neutron-metadata-agent', 'neutron-openvswitch-agent', 'neutron-server', 'neutron-server-ovn', 'neutron-sriov-agent']}, {'nova-base': ['nova-api', 'nova-compute', 'nova-compute-ironic', 'nova-conductor', 'nova-libvirt', 'nova-novncproxy', 'nova-scheduler']}, {'novajoin-base': ['novajoin-notifier', 'novajoin-server']}, {'octavia-base': ['octavia-api', 'octavia-health-manager', 'octavia-housekeeping', 'octavia-worker']}, 'placement-api', {'swift-base': ['swift-account', 'swift-container', 'swift-object', 'swift-proxy-server']}, 'tempest', 'zaqar-wsgi']}]

It didn't failed the ansible run :(.