[8.0](backport #28817) Remove Docker input from Filebeat

[mergify]

This is an automatic backport of pull request #28817 done by Mergify.

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[elasticmachine]

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• Start Time: 2021-11-08T08:10:03.499+0000

• Duration: 98 min 7 sec

• Commit: f7aca66

Test stats 🧪

Test	Results
Failed	0
Passed	14944
Skipped	2324
Total	17268

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