Drop support for RHEL 7 / CentOS 7 (#11246)

* Simplify docker systemd unit

systemd handles missing unit by ignoring the dependency so we don't need
to template them.

* Remove RHEL 7/CentOS 7 support

- remove ref in kubespray roles
- move CI from centos 7 to 8
- remove docs related to centos7

* Remove container-storage-setup

Only used for RHEL 7 and CentOS 7

roles/kubernetes/preinstall/defaults/main.yml

@@ -139,6 +139,3 @@ systemd_resolved_disable_stub_listener: "{{ ansible_os_family in ['Flatcar', 'Fl
 # Used to disable File Access Policy Daemon service.
 # If service is enabled, the CNI plugin installation will fail
 disable_fapolicyd: true
-
-# Enable 0120-growpart-azure-centos-7 tasks
-growpart_azure_enabled: true

roles/kubernetes/preinstall/tasks/0120-growpart-azure-centos-7.yml

@@ -1,44 +0,0 @@
----
-
-# Running growpart seems to be only required on Azure, as other Cloud Providers do this at boot time
-
-- name: Install growpart
-  package:
-    name: cloud-utils-growpart
-    state: present
-
-- name: Gather mounts facts
-  setup:
-    gather_subset: 'mounts'
-
-- name: Search root filesystem device
-  vars:
-    query: "[?mount=='/'].device"
-    _root_device: "{{ ansible_mounts | json_query(query) }}"
-  set_fact:
-    device: "{{ _root_device | first | regex_replace('([^0-9]+)[0-9]+', '\\1') }}"
-    partition: "{{ _root_device | first | regex_replace('[^0-9]+([0-9]+)', '\\1') }}"
-    root_device: "{{ _root_device }}"
-
-- name: Check if growpart needs to be run
-  command: growpart -N {{ device }} {{ partition }}
-  failed_when: false
-  changed_when: "'NOCHANGE:' not in growpart_needed.stdout"
-  register: growpart_needed
-  environment:
-    LC_ALL: C
-
-- name: Check fs type
-  command: file -Ls {{ root_device }}
-  changed_when: false
-  register: fs_type
-
-- name: Run growpart  # noqa no-handler
-  command: growpart {{ device }} {{ partition }}
-  when: growpart_needed.changed
-  environment:
-    LC_ALL: C
-
-- name: Run xfs_growfs  # noqa no-handler
-  command: xfs_growfs {{ root_device }}
-  when: growpart_needed.changed and 'XFS' in fs_type.stdout

roles/kubernetes/preinstall/tasks/main.yml

@@ -130,16 +130,6 @@
   tags:
     - bootstrap-os
 
-- name: Grow partition on azure CentOS
-  import_tasks: 0120-growpart-azure-centos-7.yml
-  when:
-    - not dns_late
-    - azure_check.stat.exists
-    - ansible_os_family == "RedHat"
-    - growpart_azure_enabled
-  tags:
-    - bootstrap-os
-
 - name: Run calico checks
   include_role:
     name: network_plugin/calico

roles/kubernetes/preinstall/vars/main.yml

@@ -93,11 +93,8 @@ pkgs:
   python3-libselinux:
     os:
       distributions:
-        RedHat: &major_redhat_like
-          major_versions:
-          - "8"
-          - "9"
-        CentOS: *major_redhat_like
+        RedHat: {}
+        CentOS: {}
   rsync: {}
   socat: {}
   software-properties-common: *debian_family_base