[PG13] Test upgrade in db-benchmarking, without load

Please test the switchover process with the logical replication in place in the benchmark environment

The goal is to use both playbooks and be aware of he results, and in case is needed create or adjust the improvements.

Missing parts

• Playbook for the pg_upgrade step
• switchover.yml - Optimize: TASK [(SOURCE) Get the sequence value] and TASK [(TARGET) Increase the value of sequences, need to be significant faster We decided to estimate a good static value and use this, for instead.
• Document why the TL inc is +2
  • +1 - we perform a promote after reaching recovery_target_lsn
  • +2 - the Patroni does it himself by starting the server first as a replica and then executing the promote after he received the leader's key
• Validate the mitigation to prevent doublets caused by sequences is effective

Acceptance criteria:

• Execute the logical and switchover playbook in the benchmark environment