Update on Studies and multi-file upload

[Kerem-G]

Studies workflow currently adds new files on update. Overwrite value for SynbioHub is invalid on studies workflow for when using the same workflow to upload changes to old files. Also noting that the studies workflow should utilize the multi-dropzone instead of the singular dropzone in order to upload multiple files at once.

[Kerem-G]

Also noting that the files list that is seen on the results page should be updated to include the names of the attachments files as well.