[containerd] Allow configuring base_runtime_spec per containerd runtime (#9302)

and supply a default runtime spec.

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

@@ -84,6 +84,15 @@
   notify: restart containerd
   when: http_proxy is defined or https_proxy is defined
 
+- name: containerd | Write base_runtime_specs
+  copy:
+    content: "{{ item.value }}"
+    dest: "{{ containerd_cfg_dir }}/{{ item.key }}"
+    owner: "root"
+    mode: 0644
+  with_dict: "{{ containerd_base_runtime_specs | default({}) }}"
+  notify: restart containerd
+
 - name: containerd | Copy containerd config file
   template:
     src: config.toml.j2