Gitlab upgrade from 15 to 16

Recipe: gitlab-kas::enable
  * runit_service[gitlab-kas] action restart (up to date)

Running handlers:
[2024-02-09T12:37:23+00:00] ERROR: Running exception handlers
There was an error running gitlab-ctl reconfigure:

rails_migration[gitlab-rails] (gitlab::database_migrations line 51) had an error: Mixlib::ShellOut::ShellCommandFailed: bash_hide_env[migrate gitlab-rails database] (gitlab::database_migrations line 20) had an error: Mixlib::ShellOut::ShellCommandFailed: Expected process to exit with [0], but received '1'
---- Begin output of "bash"  ----
STDOUT: rake aborted!
ActiveRecord::DatabaseConnectionError: There is an issue connecting to your database with your username/password, username: gitlab.

Please check your database configuration to ensure the username/password are valid.
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/load_balancer.rb:124:in `read_write'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:126:in `write_using_load_balancer'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:96:in `method_missing'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:130:in `configure_database'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:107:in `configure_pg_databases'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:94:in `block (3 levels) in <top (required)>'
/opt/gitlab/embedded/bin/bundle:25:in `load'
/opt/gitlab/embedded/bin/bundle:25:in `<main>'

Caused by:
PG::ConnectionBad: connection to server on socket "/var/opt/gitlab/postgresql/.s.PGSQL.5432" failed: Connection refused
        Is the server running locally and accepting connections on that socket?
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/load_balancer.rb:124:in `read_write'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:126:in `write_using_load_balancer'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:96:in `method_missing'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:130:in `configure_database'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:107:in `configure_pg_databases'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:94:in `block (3 levels) in <top (required)>'
/opt/gitlab/embedded/bin/bundle:25:in `load'
/opt/gitlab/embedded/bin/bundle:25:in `<main>'
Tasks: TOP => gitlab:db:configure
(See full trace by running task with --trace)
STDERR: 
---- End output of "bash"  ----
Ran "bash"  returned 1

# su - gitlab-psql

$ postgres -D /var/opt/gitlab/postgresql/data
2024-02-09 12:58:49.298 GMT [2748] LOG:  unrecognized configuration parameter "wal_keep_segments" in file "/var/opt/gitlab/postgresql/data/runtime.conf" line 30
2024-02-09 12:58:49.298 GMT [2748] FATAL:  configuration file "/var/opt/gitlab/postgresql/data/runtime.conf" contains errors