Temporary Ansible-generated SSH keys for postgres aren't removed after upgrade

[bkhomuts]

Bug description

After upgrading the cluster with pg_upgrade, temporary Ansible-generated SSH keys, which were created during the upgrade, remain.

Expected behavior

The SSH keys must be cleaned up after the upgrade is complete, or if PostgreSQL version rolled back.

Steps to reproduce

1. Do major version upgrade with pg_upgrade
2. Check ~/.ssh/authorized_keys file --- keys will remain

Installation method

Command line

System info

Debian 13
Autobase from Git (bc942b0).

Additional info

No response

[vitabaks]

We should delete it only if the enable_ssh_key_based_authentication option is not enabled.

for example, I use SSH Key-Based Authentication in my clusters.

[bkhomuts]

In my case enable_ssh_key_based_authentication is disabled by default, and I log into the cluster using a different, non-postgres user.
As the keys are being created as part of upgrade for the purpose of upgrade, my expectation is that those keys will have to be removed after the upgrade process is complete (success or failure) as a clean-up.
Important to remove those keys for hardening --- preventing compromise of other servers, if one of the servers have been breached.

[vitabaks]

feel free to suggest a PR