Incorrect thumbnail path at Vercel

[buccalon]

Hi @edsilv, thanks for coming up with this project

Using biiif-template I found two broken thumbnail paths when deployed at Vercel:

1. Root collection has /collection/ on its thumbnail path, but the image is actually at the root level:
   

2. Canvas thumbnail has the canvas path before the manifest path:
   

For debugging purposes, please check these manifests:

• Collection: https://iiif.tiju.ca/
• Item Manifest: https://iiif.tiju.ca/1938-debate-maya/

I assume this issue is related to this commit, however I don't know how to fix it.

Could you please guide me on a solution?