* rename ansible groups to use _ instead of -

k8s-cluster -> k8s_cluster
k8s-node -> k8s_node
calico-rr -> calico_rr
no-floating -> no_floating

Note: kube-node,k8s-cluster groups in upgrade CI
      need clean-up after v2.16 is tagged

* ensure old groups are mapped to the new ones

* Set containerd version to 1.4.3

* Set containerd version to 1.4.4

Co-authored-by: Barry Melbourne <9964974+bmelbourne@users.noreply.github.com>

* update containerd documentation with etcd change

* update conterind docs

* containerd docker hub registry mirror support

* add docs

* fix typo

* fix yamllint

* fix indent in sample
and ansible-playbook param in testcases_run

* fix md

* mv common vars to tests/common/_docker_hub_registry_mirror.yml

* checkout vars to upgrade tests