Fix CI job artifacts metadata not extracting on some S3 providers

This updates Workhorse to v8.39.0 to fix an issue with
`gitlab-zip-metadata`.

This relates to https://gitlab.com/gitlab-org/gitlab/-/issues/223806.

Full list of Workhorse changes:
https://gitlab.com/gitlab-org/gitlab-workhorse/-/blob/master/CHANGELOG

GITLAB_WORKHORSE_VERSION

-8.38.0
+8.39.0

changelogs/unreleased/sh-update-workhorse-8-39.yml

+---
+title: Fix CI job artifacts metadata not extracting on some S3 providers
+merge_request: 39345
+author:
+type: fixed