Don't write on shared FS when OS in enabled

What does this MR do?

When direct_upload enabled we are still dumping a local copy of the file on disk.

This MR disables this behavior.

Workhorse will be instructed to write the file on disk only when direct_upload is disabled.

Related to #22547 (closed) - based on gitlab-foss!19712 (closed)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Performance and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers