Do not fail when the registry is offline.

tasks/deploy_reverse-proxy.yml

@@ -109,6 +109,8 @@
     password: "{{ private_registry_password }}"
     registry: "{{ private_registry_domain }}"
   changed_when: false
+  # We ignore failures because the image should be in the cache
+  failed_when: false
   become: true
 
 - name: Create reverse-proxy container