Verify active scan rules can be excluded

What does this MR do?

DAST Active scan rules can be excluded by editing the Default Policy.policy in the /home/zap/.ZAP_D/policies directory on the DAST image.

This MR verifies this is the case by altering a test to exclude a rule.

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