+ added as separator character on direct-from-S3 downloads

[djbrooke]

• signs are being added to file names when they are being downloaded on the release candidate. To reproduce:

• Go to https://dataverse5.odum.unc.edu/file.xhtml?fileId=1884&version=DRAFT
• Click the download button for the file "spaces space spaces"
• Note that the files downloads as spaces+space+spaces.png

vs. Demo:

• Go to https://demo.dataverse.org/dataset.xhtml?persistentId=doi:10.70122/FK2/1WW7LI
• Click the download button for the file "spaces space spaces"
• Note that the files downloads as spaces space spaces.png

[qqmyers]

FWIW - The 303 redirect being sent from Dataverse to have the browser retrieve from S3 is:
Location: https://odum-dataverse5-test.s3.amazonaws.com/10.5072/FK2/AT8YFM/173dee3e434-a1e19d09f707?response-content-disposition=attachment%3B%20filename%2A%3DUTF-8%27%27spaces%2Bspace%2Bspaces.png&response-content-type=image%2Fpng&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20200811T193433Z&X-Amz-SignedHeaders=host&X-Amz-Expires=3600&X-Amz-Credential=AKIAJOOKUO5J7RCRR65A%2F20200811%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=6a9d8ed2f8331793011f0331fa68d1660e5bf944cdeac8d6ab45ea8e590eb748

[djbrooke]

The dwellers of the dv-tech slack channel talked through this and suggested re-testing on production (dataverse.harvard.edu) where there is a redirect to S3. Sure enough, in production the + is shown.

For now, I'll leave this open because I think renaming files is weird, but it's not something that needs to be resolved for Dataverse 5. @scolapasta pointed out that people may not run into issues here because zipping keeps the file names as expected.

[qqmyers]

Looks like it was introduced in #4542 as part of the solution to UTF-8 chars...