Use the correct script location for the build trigger script

What does this MR do?

Fixes an error in the ci job that triggers the cng images on a tag

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Tag triggers are failing in 11.1 : https://gitlab.com/gitlab-org/gitlab-ee/-/jobs/80018041

In 11.0.x we were using a different script for this that is working, but we changed the script in 11.1, and haven't quite gotten the job fully updated yet.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
  • Has been reviewed by a Database specialist
• Conform by the merge request performance guides
• Conform by the style guides
• Conform by the database guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?