Update Workhorse version to 8.51.0

What does this MR do?

Updates Workhorse version: https://gitlab.com/gitlab-org/gitlab-workhorse/-/tags/v8.51.0

Workhorse Changelog:

## v8.51.0

### Changed
- Allow configure image resizing params
  https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/615

### Fixed
- Fix processing lsif dump with repeating lines with inVs
  https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/621
  Contributed by Pavel Kuznetsov

### Other
- Add CODEOWNERS with listed maintainers
  https://gitlab.com/gitlab-org/gitlab-workhorse/-/merge_requests/623

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

N/A

Security

N/A