fix: use .tar.gz extension for RKE2 airgap tarballs from Pulp

Pulp downloads and stores RKE2 airgap image tarballs as .tar.gz
regardless of the original .tar.zst extension in the source URL.
Update the NFS config download tasks to use .tar.gz when fetching
from the local Pulp mirror.

Signed-off-by: John Lockman <jlockman3@gmail.com>

Author: j0hnL

provision/roles/k8s_config/tasks/create_compute_rke2_config_nfs.yml

@@ -185,8 +185,8 @@
 # RKE2 airgap system images (core + selected CNI)
 - name: Download RKE2 airgap image tarballs to compute NFS share
   ansible.builtin.get_url:
-    url: "{{ offline_tarball_path }}/{{ item }}/{{ item }}.tar.zst"
-    dest: "{{ compute_k8s_client_mount_path }}/rke2/images/{{ item }}.tar.zst"
+    url: "{{ offline_tarball_path }}/{{ item }}/{{ item }}.tar.gz"
+    dest: "{{ compute_k8s_client_mount_path }}/rke2/images/{{ item }}.tar.gz"
     mode: "{{ file_mode }}"
     validate_certs: false
   loop:

provision/roles/k8s_config/tasks/create_rke2_config_nfs.yml

@@ -276,8 +276,8 @@
 # on the nodes; the cloud-init templates copy these from the NFS share.
 - name: Download RKE2 airgap image tarballs to NFS share
   ansible.builtin.get_url:
-    url: "{{ offline_tarball_path }}/{{ item }}/{{ item }}.tar.zst"
-    dest: "{{ k8s_client_mount_path }}/rke2/images/{{ item }}.tar.zst"
+    url: "{{ offline_tarball_path }}/{{ item }}/{{ item }}.tar.gz"
+    dest: "{{ k8s_client_mount_path }}/rke2/images/{{ item }}.tar.gz"
     mode: "{{ file_mode }}"
     validate_certs: false
   loop: