[FEATURE REQUEST] [PostgreSQL] [upgrade] Do not remove new packages automatically in rollback

[to-bar]

Is your feature request related to a problem? Please describe.
When PostgreSQL upgrade fails, Epiphany performs automatic rollback (Ansible rescue block) during which the following operations are done:

• remove PostgreSQL related packages (new version)
• remove new version data directory
• restore repmgr symlinks
• start and enable old PostgreSQL service
• start and enable old repmgr service

When operator wants to debug/analyze a failure, there is no new binaries, so reproducing an issue (re-run the failed command) is difficult.

Describe the solution you'd like

The rollback creates a file (can be script) with instructions how to uninstall new binaries instead removing them automatically.

Describe alternatives you've considered
No automatic rollback, all commands in a file.

Additional context
The upgrade is run based on the condition: when: not pg_data_dir.stat.exists or pg_data_dir_files.matched == 0.
So the rollback must remove files from data dir.

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DoD checklist

• Changelog updated
• COMPONENTS.md updated / doesn't need to be updated
• Schema updated / doesn't need to be updated
• Feature has automated tests
• Automated tests passed (QA pipelines)
  • apply
  • upgrade
• Idempotency tested
• Documentation added / updated / doesn't need to be updated
• All conversations in PR resolved
• Solution meets requirements and is done according to design doc
• Usage compliant with license
• Backport tasks created / doesn't need to be backported

[rafzei]

🚀

[mkyc]

Before merging PR for this task decide with @przemyslavic if it can be merged to 1.2.0 release branch.

[przemyslavic]

✔️ Tested apply and upgrade from v1.0.x to v1.3.0dev with rollback procedure,
Single-node installation and cluster deployment with replication enabled have been checked.