T5657: Add VRF support for zabbix-agent

[sever-sever]

To start the service under VRF requires starting under User=root otherwise it had issues with cgroups

Change Summary

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T5657

Related PR(s)

Component(s) name

zabbix-agent

Proposed changes

How to test

set service monitoring zabbix-agent host-name 'r4'
set service monitoring zabbix-agent server '192.168.122.1'
set service monitoring zabbix-agent vrf 'mgmt'

Check the service:

vyos@r4# sudo systemctl status zabbix-agent2
● zabbix-agent2.service - Zabbix Agent 2
     Loaded: loaded (/lib/systemd/system/zabbix-agent2.service; disabled; preset: enabled)
    Drop-In: /run/systemd/system/zabbix-agent2.service.d
             └─10-override.conf
     Active: active (running) since Wed 2024-07-31 18:01:38 EEST; 23min ago
       Docs: man:zabbix_agent2
   Main PID: 11452 (zabbix_agent2)
      Tasks: 9 (limit: 18718)
     Memory: 15.9M
        CPU: 191ms
     CGroup: /system.slice/zabbix-agent2.service
             └─vrf
               └─mgmt
                 └─11452 /usr/sbin/zabbix_agent2 --config /run/zabbix/zabbix-agent2.conf --foreground

Smoketest result

vyos@r4:~$ /usr/libexec/vyos/tests/smoke/cli/test_service_monitoring_zabbix-agent.py
test_01_zabbix_agent (__main__.TestZabbixAgent.test_01_zabbix_agent) ... ok

----------------------------------------------------------------------
Ran 1 test in 13.460s

OK
vyos@r4:~$

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

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No issues in PR Title / Commit Title

[github-actions]

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warning: Unused directories imported from vyos.defaults in src/conf_mode/system_console.py:25.