Revert "Try with postgres"

This reverts commit b521aff613.

Actually, I can make it work. Stick with mysql

ansible/pre-deploy.yml

@@ -15,27 +15,27 @@
           - id.autonomic.zone
         state: present
 
-    - name: Create postgres database
-      shell: "dokku postgres:create keycloak --password {{ db_passwd }} --root-password {{ root_db_passwd }}"
+    - name: Create mariadb database
+      shell: "dokku mariadb:create keycloak --password {{ db_passwd }} --root-password {{ root_db_passwd }}"
       args:
-        creates: /var/lib/dokku/services/postgres/keycloak
+        creates: /var/lib/dokku/services/mariadb/keycloak
 
-    - name: Specify postgres docker volume mounts
+    - name: Specify mariadb docker volume mounts
       dokku_storage:
         app: keycloak
         mounts:
-          - /var/lib/dokku/services/postgres/keycloak:/var/lib/mysql
+          - /var/lib/dokku/services/mariadb/keycloak:/var/lib/mysql
 
     - name: Configure the dokku app environment
       dokku_config:
         app: keycloak
         restart: false
         config:
-          DB_ADDR: "dokku-postgres-keycloak"
+          DB_ADDR: "dokku-mariadb-keycloak"
           DB_DATABASE: "keycloak"
           DB_PASSWORD: "{{ db_passwd }}"
-          DB_USER: "postgres" # https://github.com/dokku/dokku-mariadb/issues/89
-          DB_VENDOR: "postgres"
+          DB_USER: "mariadb" # https://github.com/dokku/dokku-mariadb/issues/89
+          DB_VENDOR: "mariadb"
           DOKKU_LETSENCRYPT_EMAIL: "{{ autonomic_admin_mail }}"
           KEYCLOAK_PASSWORD: "{{ autonomic_admin_pass }}"
           KEYCLOAK_USER: "{{ autonomic_admin_user }}"