feat: Add shell provisioner to fix yum base url

fix yum install failures by fixing the baseurl via shell provisioners
temporarily until we upgrade the base OS

openstack-proxy/nodeimage.pkr.hcl

@@ -36,6 +36,13 @@ source "openstack" "image" {
 build {
   sources = ["source.openstack.image"]
 
+  provisioner "shell" {
+    inline = [
+      "sed -i 's/^mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*",
+      "sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*"
+    ]
+  }
+
   provisioner "ansible" {
     use_proxy        = false
     user             = var.ssh_username