CI: Use main Rocky mirror

We are frequently hitting issues downloading the mirrorlist in CI.  This
copies the change from kolla-ansible[1] with the hope that it will
improve reliability.

[1] https://review.opendev.org/c/openstack/kolla-ansible/+/983965

Change-Id: Ic107bc1e21806cc6549ac86d8ccc83377fe2cfba
Signed-off-by: Will Szumski <will@stackhpc.com>
(cherry picked from commit 71dee31)

Author: jovial

roles/kayobe-ci-prep/tasks/main.yml

@@ -1,4 +1,10 @@
 ---
+- name: Set Rocky Linux mirror to download.rockylinux.org
+  become: true
+  ansible.builtin.shell:
+    cmd: sed -i 's/mirrorlist/#mirrorlist/g; s/#baseurl/baseurl/g' /etc/yum.repos.d/rocky.repo
+  when: ansible_facts.distribution == "Rocky"
+
 - block:
     - name: Install dbus for debian system
       apt:
@@ -25,7 +31,7 @@
         name: dnf-plugins-core
         state: present
 
-    - name: Enable the EPEL repository
+    - name: Disable the EPEL repository
       command: dnf config-manager --disable epel
 
     - name: Install packages needed for unprivileged mode