Fix systemd service files issues

[alamashir]

This commit addresses multiple bugs in systemd service files reported in issue #53706:

1. Fix incorrect command in airflow-api.service

   • Changed 'airflow api' to 'airflow api-server' (correct CLI command)

2. Standardize environment configuration approach

   • Changed airflow-api.service and airflow-triggerer.service to use EnvironmentFile=/etc/sysconfig/airflow instead of inline Environment
   • This provides consistency with other services and allows admins flexibility to manage custom environment variables centrally

3. Fix service dependencies

   • Added proper After= and Wants= clauses for database and message queue services (postgresql, mysql, redis, rabbitmq) to airflow-api.service and airflow-triggerer.service
   • Services now wait for required dependencies before starting

4. Additional bug fixes discovered during review

   • airflow-flower.service: Removed duplicate ExecStart line
   • airflow-kerberos.service: Fixed command from 'kerberos' to 'airflow kerberos'

5. Consistency improvements

   • Added Type=simple and RestartSec=5s to airflow-api.service and airflow-triggerer.service for consistency with other services

All systemd service files now follow the same configuration pattern, making them easier to maintain and more reliable during system startup.

Fixes #53706

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[jscheffl]

Thanks for the fix. Interesting, from what I see this would have never worked.

I am not a systemd expert but from pure reading this looks like LGTM. Another pair of eyes might be good.

[boring-cyborg]

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[github-actions]

Backport successfully created: v3-1-test

Status	Branch	Result
✅	v3-1-test