Support SECURE_ANALYZERS_PREFIX variable in API Security templates

What does this MR do and why?

Describe in detail what your merge request does and why.

An error in how the stable templates are written prevents the use of SECURE_ANALYZERS_PREFIX to change the container registry for API Security in the DAST API and API Fuzzing templates.

This is a breaking change made to the latest version of both templates.

Related to #343489 (closed)

• Add DAST-API.latest template
• Correct issue in both DAST-API.latest and API-Fuzzing.latest
• Add tests for DAST-API.latest
• Update tests for API-Fuzzing.latest
• Changes are breaking
• Test project for DAST API
  • Project
  • CI Template
  • Job
  • 
• Test project for API Fuzzing
  • Project
  • CI Template
  • Job
  • 

Screenshots or screen recordings

latest versions of the CI templates don't display in the UI.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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