Get ansible-collection-atmosphere running in a internal environment.

Change the DNS suffix and ACME server. Both with the goal to get in this ansible-collection-atmosphere
running in internal environments.

Sem-Ver: feature
Change-Id: I43cf67ba32785c8e3f69e24f55bdc9d5ec22b75d
diff --git a/roles/cert_manager/defaults/main.yml b/roles/cert_manager/defaults/main.yml
index 508c527..bb76a1c 100644
--- a/roles/cert_manager/defaults/main.yml
+++ b/roles/cert_manager/defaults/main.yml
@@ -14,7 +14,7 @@
 # .. envvar:: cert_manager_acme_server [[[
 #
 # ACME server URL
-cert_manager_acme_server: https://acme-v02.api.letsencrypt.org/directory
+cert_manager_acme_server: "{{ lookup('env', 'ATMOSPHERE_ACME_SERVER') | default('https://acme-v02.api.letsencrypt.org/directory', True) }}"
 
                                                                    # ]]]
 # .. envvar:: cert_manager_issuer [[[