Updating proxysql.yaml.j2 to use mariadb_port for backends

Related-Bug: #2024554
Change-Id: Ie678d90f88034a079f3284ab5a509be24e8eb42b

ansible/roles/loadbalancer/templates/proxysql/proxysql.yaml.j2

@@ -30,7 +30,7 @@ mysql_servers:
 {% set WEIGHT = 10 %}
 {% endif %}
   - address: "{{ 'api' | kolla_address(host) }}"
-    port :  {{ database_port }}
+    port :  {{ mariadb_port }}
     hostgroup :  {{ WRITER_GROUP }}
     max_connections: {{ proxysql_backend_max_connections }}
     max_replication_lag: {{ proxysql_backend_max_replication_lag }}

releasenotes/notes/proxysql-template-mariadb-port-cf8f2d88c0962b75.yaml

+---
+fixes:
+  - |
+    Updates ``proxysql.yaml.j2`` to use mariadb_port for backends.
+    This fixes setups where ``database_port`` and ``mariadb_port`` differ.