specs/filebeat.spec.yml - Re-add lumberjack input

[andrewkroh]

What does this PR do?

Between v8.5.3 and v8.6.0 the lumberjack input was lost from the filebeat spec file.

From v8.5.3:

elastic-agent/internal/spec/filebeat.yml

Line 49 in c0367b9

- lumberjack

Why is it important?

The barracuda_cloudgen_firewall integration depends on this input type.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Related issues

• Relates [barracuda_cloudgen_firewall] Package broken for Elastic Agent >= 8.6.0  integrations#5912

Logs

From v8.6.0 when running https://docs.elastic.co/integrations/barracuda_cloudgen_firewall.

{
  "@timestamp": "2023-04-18T17:03:46.412Z",
  "component": {
    "id": "lumberjack-default",
    "state": "FAILED"
  },
  "ecs.version": "1.6.0",
  "log.level": "error",
  "log.origin": {
    "file.line": 833,
    "file.name": "coordinator/coordinator.go"
  },
  "message": "Spawned new unit lumberjack-default: input not supported",
  "unit": {
    "id": "lumberjack-default",
    "state": "FAILED",
    "type": "output"
  }
}

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• Start Time: 2023-04-18T19:17:53.754+0000

• Duration: 17 min 50 sec

Test stats 🧪

Test	Results
Failed	0
Passed	5535
Skipped	19
Total	5554

💚 Flaky test report

Tests succeeded.

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[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.529% (67/68)	👍
Files	68.22% (161/236)	👍
Classes	67.785% (303/447)	👍
Methods	54.111% (928/1715)	👍
Lines	39.612% (10503/26515)	👎 -0.008
Conditionals	100.0% (0/0)	💚

[andrewkroh]

/test

[andrewkroh]

Is anything else needed on this? If not, could someone from the Agent team merge this please.