Add tasks to configure external services only

This change allows specific playbooks to configure their haproxy
service(s) separately by running the role and using tasks_from to
execute just the service template installation code path.

Change-Id: I88ce0eb92784b3d3a0d1a952e95a8eb1fa376e77
Co-Authored-By: Damian Dąbrowski <damian@dabrowski.cloud>

tasks/haproxy_service_config_external.yml

@@ -0,0 +1,35 @@
+---
+# Copyright 2023, Cleura AB
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+- name: Gather variables for each operating system
+  include_vars: "{{ lookup('first_found', params) }}"
+  vars:
+    params:
+      files:
+        - "{{ ansible_facts['distribution'] | lower }}-{{ ansible_facts['distribution_version'] | lower }}.yml"
+        - "{{ ansible_facts['distribution'] | lower }}-{{ ansible_facts['distribution_major_version'] | lower }}.yml"
+        - "{{ ansible_facts['os_family'] | lower }}-{{ ansible_facts['distribution_major_version'] | lower }}.yml"
+        - "{{ ansible_facts['distribution'] | lower }}.yml"
+        - "{{ ansible_facts['os_family'] | lower }}.yml"
+      paths:
+        - "{{ role_path }}/vars"
+
+- include_tasks: haproxy_service_config.yml
+  args:
+    apply:
+      tags:
+        - haproxy_server-config
+  tags:
+    - always