Update DAST CI Pipeline to use rules syntax

What does this MR do?

Updates the DAST pipeline to use rules syntax, instead of only/except syntax. This is required as the DAST pipeline is broken as of a recent update to GitLab rails.

Update: I couldn't get this working. I've changed the DAST Pipeline to always run these jobs.

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