qa/distros: Remove stale kubic distros

qa/distros: Remove stale kubic distros

Cause they're broken

Signed-off-by: Sebastian Wagner <sewagner@redhat.com>
(cherry picked from commit 65e2cc084073ea7e05ecbc06f5773617676708ff)

Conflicts:
	qa/distros/podman/rhel_8.3_kubic_stable.yaml
	qa/distros/podman/ubuntu_18.04_kubic_stable.yaml
	qa/distros/podman/ubuntu_20.04_kubic_stable.yaml
	qa/distros/podman/ubuntu_20.04_kubic_testing.yaml
	qa/suites/rados/cephadm/workunits/0-distro/centos_8.2_container_tools_3.0.yaml
	qa/suites/rados/cephadm/workunits/0-distro/ubuntu_20.04_kubic_stable.yaml
	qa/suites/rados/cephadm/workunits/0-distro/ubuntu_20.04_kubic_testing.yaml

Fixes: https://tracker.ceph.com/issues/53106