Disable docker-ce yum repo by default / cleanups (#7080)

Upgrading docker / containerd without adapting the configuration might break the node,
so disable docker-ce repo by default.
We are already using dpkg hold for Debian.

All containerd.io packages provide /usr/bin/runc, so no need to check

yum_conf was never used for containerd

module_hotfixes should not be needed with the EL8 repo

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

roles/container-engine/containerd/tasks/containerd_repo.yml

@@ -65,18 +65,3 @@
   when:
     - ansible_distribution in ["CentOS","RedHat"]
     - yum_result.results | length == 0
-
-- name: Copy yum.conf for editing
-  copy:
-    src: "{{ yum_conf }}"
-    dest: "{{ containerd_yum_conf }}"
-    remote_src: yes
-  when: ansible_distribution in ["CentOS","RedHat"]
-
-- name: Edit copy of yum.conf to set obsoletes=0
-  lineinfile:
-    path: "{{ containerd_yum_conf }}"
-    state: present
-    regexp: '^obsoletes='
-    line: 'obsoletes=0'
-  when: ansible_distribution in ["CentOS","RedHat"]