Fix conntrack for opensuse and docker support (#5880)

.gitlab-ci/packet.yml

Vagrantfile

roles/bootstrap-os/tasks/bootstrap-opensuse.yml

roles/bootstrap-os/tasks/main.yml

roles/container-engine/docker/templates/docker.service.j2

roles/kubernetes/preinstall/defaults/main.yml

roles/kubernetes/preinstall/vars/centos.yml

roles/kubernetes/preinstall/vars/debian.yml

roles/kubernetes/preinstall/vars/fedora.yml

roles/kubernetes/preinstall/vars/redhat.yml

roles/kubernetes/preinstall/vars/suse.yml

roles/kubernetes/preinstall/vars/ubuntu.yml