fix(kafka): Fix internal docker connection

[mdelapenya]

What does this PR do?

Follow-up of #2490 in order to be able to push commits and make progress.

Why is it important?

Give importance to @catinapoke's work in #2490, keeping the commits (and authorship), and doing the toil tasks for them. This way we can push to this feature branch (the original PR is using the main branch, so we cannot update it)

Related issues

• Supersedes #2490

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[mdelapenya]

@stevenh I addressed the majority of your comments: all except those related to the TestKafka_networkConnectivity test, which is still failing for me locally.