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/bootstrap-os/tasks/centos.yml

@@ -80,40 +80,13 @@
     - { option: "name", value: "CentOS-{{ ansible_distribution_major_version }} - Extras" }
     - { option: "enabled", value: "1" }
     - { option: "gpgcheck", value: "0" }
-    - { option: "baseurl", value: "http://vault.centos.org/{{ 'altarch' if (ansible_distribution_major_version | int) <= 7 and ansible_architecture == 'aarch64' else 'centos' }}/{{ ansible_distribution_major_version }}/extras/$basearch/{% if ansible_distribution_major_version | int > 7 %}os/{% endif %}" }
+    - { option: "baseurl", value: "http://mirror.centos.org/centos/{{ ansible_distribution_major_version }}/extras/$basearch/os/" }
   when:
     - use_oracle_public_repo | default(true)
     - '''ID="ol"'' in os_release.stdout_lines'
     - (ansible_distribution_version | float) >= 7.6
     - (ansible_distribution_version | float) < 9
 
-# CentOS 7 EOL at July 1, 2024.
-- name: Check CentOS-Base.repo exists for CentOS 7
-  stat:
-    path: /etc/yum.repos.d/CentOS-Base.repo
-  register: centos_base_repo_stat
-  when:
-    - ansible_distribution_major_version == "7"
-
-# CentOS 7 EOL at July 1, 2024.
-- name: Update CentOS 7 CentOS-Base.repo
-  when:
-    - ansible_distribution_major_version == "7"
-    - centos_base_repo_stat.stat.exists
-  become: true
-  block:
-    - name: Disable CentOS 7 mirrorlist in CentOS-Base.repo
-      replace:
-        path: "{{ centos_base_repo_stat.stat.path }}"
-        regexp: '^mirrorlist='
-        replace: '#mirrorlist='
-
-    - name: Update CentOS 7 baseurl in CentOS-Base.repo
-      replace:
-        path: "{{ centos_base_repo_stat.stat.path }}"
-        regexp: '^#baseurl=http:\/\/mirror.centos.org'
-        replace: 'baseurl=http:\/\/vault.centos.org'
-
 # CentOS ships with python installed
 
 - name: Check presence of fastestmirror.conf

roles/bootstrap-os/tasks/redhat.yml

@@ -62,17 +62,6 @@
     - rh_subscription_username is defined
     - rh_subscription_status.changed
 
-# container-selinux is in extras repo
-- name: Enable RHEL 7 repos
-  community.general.rhsm_repository:
-    name:
-      - "rhel-7-server-rpms"
-      - "rhel-7-server-extras-rpms"
-    state: "{{ 'enabled' if (rhel_enable_repos | default(True) | bool) else 'disabled' }}"
-  when:
-    - ansible_distribution_major_version == "7"
-    - (not rh_subscription_status.changed) or (rh_subscription_username is defined) or (rh_subscription_org_id is defined)
-
 # container-selinux is in appstream repo
 - name: Enable RHEL 8 repos
   community.general.rhsm_repository: