Merge branch 't33389-double-failover-test' into 'master'

double failover test using postgres-maintenance role, refs #33389

See merge request mediaserver/envsetup!43

ansible/playbooks/postgres-maintenance/standby_to_primary.yml

+#!/usr/bin/env ansible-playbook
+---
+- name: POSTGRESQL SWITCH CURRENT STANDBY TO PRIMARY
+  hosts: postgres_standby
+  tasks:
+    - name: fail if node status if not standby
+      fail:
+        msg: "Current status {{ rephacheck['stdout'] }} must be standby."
+      when: rephacheck['stdout'] != "standby"
+    - name: check if node is currently in standby
+      command: "repmgr standby switchover -f /etc/postgresql/11/main/repmgr.conf --siblings-follow --dry-run"
+      become: true
+      become_user: postgres
+      when: rephacheck['stdout'] == "standby"
+      register: standby_dry_run
+    - name: switch standby node to primary
+      command: "repmgr standby switchover -f /etc/postgresql/11/main/repmgr.conf --siblings-follow"
+      become: true
+      become_user: postgres
+      when:
+        - standby_dry_run is succeeded
+        - rephacheck['stdout'] == "standby"
+
+...