[CI] Fix testing inventory template due Ansible 2.16.14 breakage

Ansible 2.16.14 includes a fix for CVE-2024-11079 [1], which results
in the following error:

    jinja2.exceptions.UndefinedError:
        'ansible.vars.hostvars.HostVarsVars
         object' has no attribute 'ansible_host'

This issue occurs because Ansible now includes `localhost` in
`hostvars` without the `ansible_host` variable set, which
unexpectedly breaks our test inventory rendering.

This patch adds a filter to exclude `localhost`
during the rendering process, as it is irrelevant for our purposes.

[1] ansible/ansible#84353

Change-Id: Ie7ae47e5a624da31cf6cc5cd3c9239450487b8ed
(cherry picked from commit 0298699)

requirements.yml

@@ -2,4 +2,4 @@
 collections:
   - name: https://opendev.org/openstack/ansible-collection-kolla
     type: git
-    version: stable/2023.1
+    version: unmaintained/2023.1

tests/templates/inventory.j2

@@ -11,7 +11,7 @@
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 {% else %}
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 {% endif %}
@@ -31,28 +31,28 @@ control
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 {% else %}
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 {% endif %}
 
 [storage]
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 
 [monitoring]
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 
 [deployment]
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endfor %}
 
 {% if scenario == 'cells' %}
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {% set cell_name = 'cell' ~ loop.index %}
 [{{ cell_name }}]
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }} mariadb_shard_id={{ loop.index0 % 2 }}
@@ -123,7 +123,7 @@ storage
 # In CI we want Pacemaker to run on primary and secondary (to test with HA).
 
 [hacluster]
-{% for host in hostvars %}
+{% for host in hostvars | reject('equalto', 'localhost') %}
 {% if host in ['primary', 'secondary'] %}
 {{ host }} ansible_host={{ hostvars[host]['ansible_host'] }}
 {% endif %}