Refactor database IPs to unify them across reference architectures

What does this MR do?

• Updates the 3/5k IP addresses for database services to match the others
• Reorders the IP address lists for consistency
• Updates various configs to match the above
  • Fix internal load balancer pgbouncer config on all
  • Fix gitlab-ctl patroni members output in 3/5k
  • Fix 'The following IPs are used as an example' for pgsql in 3/5k
  • Fix gitlab_rails['db_load_balancing'] in 3/5k

Related issues

No issue, however there is a support ticket where the customer noticed a conflict between the reference architectures and the db_load_balancing configuration documentation

ZD 400546 (Internal only)

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