Use value in default.conf instead of ansible_fqdn

ansible_fqdn can give us a bad value in the standalone CI job.
The right value to get the principal is the one ipa knows about -
which is in default.conf.  Use that instead.

Also, re-added the standalone to the check jobs.
Change-Id: I1852c8b745f3398154878396778487c901b0cccc

tripleo_ipa/roles/tripleo_ipa_registration/tasks/main.yml

@@ -30,7 +30,15 @@
     base_server_short_name: "{{ tripleo_ipa_base_server_fqdn.split('.')[0] }}"
     base_server_domain: "{{ tripleo_ipa_base_server_fqdn.split('.', 1)[1] }}"
     enroll_base_server: "{{ tripleo_ipa_enroll_base_server }}"
-    principal: "nova/{{ ansible_fqdn }}"
+
+- name: get the default.conf file
+  slurp:
+    src: /etc/ipa/default.conf
+  register: ipa_default_conf
+
+- name: set the principal
+  set_fact:
+    principal: "nova/{{ ipa_default_conf['content']| b64decode | regex_findall('host = (.+)')|first }}"
 
 - name: add main host to IPA with OTP
   when: enroll_base_server|bool

zuul.d/layout.yaml

@@ -4,10 +4,10 @@
       - check-requirements
       - openstack-python36-jobs
       - publish-to-pypi
-      - tripleo-standalone-multinode-ipa-pipeline
     check:
       jobs:
       - tripleo-ipa-centos-8-molecule
+      - tripleo-ci-centos-8-standalone-on-multinode-ipa
     gate:
       jobs:
       - tripleo-ipa-centos-8-molecule