[8.0](backport #28971) Add SASL/SCRAM support to the Kafka test container

[mergify]

This is an automatic backport of pull request #28971 done by Mergify.

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[elasticmachine]

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• Start Time: 2021-11-16T23:58:11.755+0000

• Duration: 116 min 33 sec

• Commit: 317ee90

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Test	Results
Failed	0
Passed	54127
Skipped	5346
Total	59473

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[mergify]

This pull request has not been merged yet. Could you please review and merge it @faec? 🙏