Fix incorrect regex used in FileUploader#extract_dynamic_path

What does this MR do?

In !3867 (merged) we enabled uploads stored in the uploads table to be migrated to object storage, but there are a number of entries in the uploads table with a path containing a secret of length 10. Geo is failing to sync file uploads with these secrets in the path. This MR fixes the regex used in FileUploader#extract_dynamic_path to parse properly paths with a secret containing 10-bytes or 32-bytes.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
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• 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
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Realted issues

Closes #209940 (closed)