Fix /zap/wrk permission issue

Related Issue(s)

• gitlab-org/gitlab#288010 (closed) (see for more details)

What does this MR do?

• creates /zap/wrk before directory permissions are set in subsequent chown

Why

• uid and gid for /zap and /zap/wrk are mixed up, resulting in a permission error (see linked issue)

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