Bump sdkman

What does this MR do?

Bump SDKMAN, and vendor the script. I couldn't find the repo where this script is stored, so I vendored it in the repo, so we can compare with previous version when updating the checksum.

What are the relevant issue numbers?

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
  • Auto-DevOps template (also in CE)
  • Job definition example
  • CI Templates (to be removed)
  • Vendored CI Templates (also in CE)
• [-] Conforms to the code review guidelines
• [-] Conforms to the Go guidelines
• Security reports checked/validated by reviewer