Add 'changed_when: false'.

tasks/retrieve_secret_vars.yml

@@ -3,6 +3,7 @@
   command: cat /etc/machine-id
   register: get_local_machine_id_output
   delegate_to: localhost
+  changed_when: false
 
 - name: set local machine-id
   ansible.builtin.set_fact:
@@ -12,6 +13,7 @@
 - name: get remote machine-id
   command: cat /etc/machine-id
   register: get_remote_machine_id_output
+  changed_when: false
 
 - name: set remote machine-id
   ansible.builtin.set_fact: