"proxyconnect tcp: tls: oversized record received with length 20527" is output when preparing images

Issue

$ sudo openstack overcloud container image prepare \
--namespace=registry.access.redhat.com/rhosp13 \
--push-destination=<undercloud IP>:8787 \
--prefix=openstack- \
--tag-from-label {version}-{release} \
-e /usr/share/openstack-tripleo-heat-templates/environments/ceph-ansible/ceph-ansible.yaml \
--set ceph_namespace=registry.access.redhat.com/rhceph \
--set ceph_image=rhceph-3-rhel7 \
--output-env-file=/home/stack/templates/overcloud_images.yaml \
--output-images-file /home/stack/local_registry_images.yaml

Error inspecting image: docker://registry.access.redhat.com/rhosp13/openstack-cinder-scheduler:latest
time="2018-12-03T11:04:02+09:00" level=fatal msg="pinging docker registry returned: Get https://registry.access.redhat.com/v2/: proxyconnect tcp: tls: oversized record received with length 20527"