Resolve "Geo: Design thumbnails are not replicated"

What does this MR do?

Fixes Geo replication for design thumbnails (introduced in !22860 (merged)).

From #218557 (comment 346088611):

Files tracked by the Upload model are segregated in Geo code by file_type. This was historically needed to differentiate also between job_artifact and lfs registry entries in the file_registry table.

This MR adds the file type for design thumbnails. Since the thumbnails have file_type of design_management/design_v432_230, we must also escape the string when forming the transfer url.

Screenshots

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

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #218557 (closed)