copr-builders: automatically unsubscribe when subscription fails

Seems the subscription manager Ansible module fails to unregister the
machine when the pool attachement fails.  This terminates our playbook,
and the whole machine - but RHSM keeps tracking the system.

roles/copr/backend/files/provision/provision_builder_tasks.yml

@@ -101,6 +101,16 @@
     - copr_red_hat_subscription_password is defined
   tags:
     - red_hat_subscription
+  ignore_errors: true
+  register: subscription
+
+- name: Cleanup subscription before failure
+  community.general.redhat_subscription:
+    state: absent
+  when: subscription.failed
+
+- fail: msg="Could not subscribe"
+  when: subscription.failed
 
 - name: install copr-builder and other latest packages
   dnf: state=latest pkg={{ packages }}