Fixes #39536 - preserve RAILS_LOG_TO_STDOUT in foreman-rake

[Alleny244]

Description

Fixes #39536.

foreman-rake runs Rails via runuser -, which starts a login shell and clears most environment variables before switching to the foreman user. As a result, RAILS_LOG_TO_STDOUT was lost during install-time rake executions, causing Rails to fall back to production.log even when stdout logging was intended.

This change preserves RAILS_LOG_TO_STDOUT across the runuser invocation. Container and RPM installs that set the variable now keep stdout logging throughout install-time rake boots and no longer create /var/log/foreman/production.log. Systems that do not set RAILS_LOG_TO_STDOUT continue using file logging as before.

Related PR: theforeman/foreman-oci-images#66

Prerequisites for testing

• A system (or container) with the foreman user and runuser available

Testing scenarios

1. Verify runuser preserves the environment

sudo RAILS_LOG_TO_STDOUT=true runuser - foreman -s /bin/bash -c 'echo "[$RAILS_LOG_TO_STDOUT]"'
# Before fix: []

sudo RAILS_LOG_TO_STDOUT=true runuser -w RAILS_LOG_TO_STDOUT - foreman -s /bin/bash -c 'echo "[$RAILS_LOG_TO_STDOUT]"'
# After fix: [true]

2. Verify foreman-rake logs to stdout

With the patched /usr/sbin/foreman-rake:

rm -f /var/log/foreman/production.log

RAILS_LOG_TO_STDOUT=true foreman-rake db:version

ls /var/log/foreman/production.log
# Expected: No such file or directory

Boot messages (for example, Rails cache backend: File) should appear on stdout.

3. Verify existing behavior is unchanged

Run foreman-rake without RAILS_LOG_TO_STDOUT:

unset RAILS_LOG_TO_STDOUT
foreman-rake db:version

Rails should continue using production.log, matching the existing behavior for traditional installations.