Update offline.yml (#9274)

Change "ubuntu_repo" to "debian_repo" for containerd_debian_repo_base_url and containerd_debian_repo_gpgkey

inventory/sample/group_vars/all/offline.yml

@@ -82,8 +82,8 @@
 # docker_debian_repo_base_url: "{{ debian_repo }}/docker-ce"
 # docker_debian_repo_gpgkey: "{{ debian_repo }}/docker-ce/gpg"
 ### Containerd
-# containerd_debian_repo_base_url: "{{ ubuntu_repo }}/containerd"
-# containerd_debian_repo_gpgkey: "{{ ubuntu_repo }}/containerd/gpg"
+# containerd_debian_repo_base_url: "{{ debian_repo }}/containerd"
+# containerd_debian_repo_gpgkey: "{{ debian_repo }}/containerd/gpg"
 # containerd_debian_repo_repokey: 'YOURREPOKEY'
 
 ## Ubuntu