Remove docker-in-docker job from API Fuzzing

What does this MR do?

Remove the apifuzzer_fuzz_dnd job. The docker-in-docker job for API Fuzzing has been deprecated. Instead users will extend the apifuzzer_fuzz job adding a services definition.

Related to #327508 (closed)

CI Template

• This change is not backwards compatible. The change has been made to the latest version of the template.
• This feature was never documented, so no documentation updates are needed.
• No test changes are needed, the docker-in-docker tests have already been removed.
• Test project:
  • Project
  • CI Template
  • Passing Job
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Does this MR meet the acceptance criteria?

Conformity

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• [-] Documentation (if required)
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• Style guides
• [-] Database guides
• Separation of EE specific content

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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
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