Update DAST release scripts

What does this MR do?

The Secure Report Format schema heavily borrows from the DAST release scripts. As another round of reviews occurred on these scripts, the code quality was greatly improved. This MR merges these changes back into the DAST repository.

There is also a requirement for DAST Docker images to be released to the analayzers/dast Docker registry. This will make it easier for offline GitLab setups to download all of GitLab Secure images. The ability to deploy to more than one registry is also included in this MR.

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE, if necessary
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
  • Job definition example
  • Vendored CI Templates (also in CE)
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer