[8.0](backport #29131) Remove Journalbeat

[mergify]

This is an automatic backport of pull request #29131 done by Mergify.

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[elasticmachine]

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• Start Time: 2021-11-30T11:03:40.747+0000

• Duration: 140 min 25 sec

• Commit: 4a1e437

Test stats 🧪

Test	Results
Failed	0
Passed	48305
Skipped	4287
Total	52592

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