Add test for content paths that have percent-encoded parts

[lidel]

Found this edge case in ipfs-inactive/bifrost-gateway#160

Content Paths with special characters are usually encoded before sending to the gateway.
However there is an edge case where a content path has already encoded parts.
We do not want it to be mangled during transport OR things like subdomain redirects.

There should be a conformance test based on below example (we dont want to pull-in entire wikipedia, but its fine to reuse the single file from /I directory as-is).

Example

The original content path is /ipns/en.wikipedia-on-ipfs.org/I/Auditorio_de_Tenerife%2C_Santa_Cruz_de_Tenerife%2C_España%2C_2012-12-15%2C_DD_02.jpg.webp (note ñ in España%2C)

But the URL path used in HTTP request is percent-encoded:

curl -v "https://en-wikipedia--on--ipfs-org.ipns.dweb.link/I/Auditorio_de_Tenerife%252C_Santa_Cruz_de_Tenerife%252C_Espa%C3%B1a%252C_2012-12-15%252C_DD_02.jpg.webp"

Test with curl (incl. subdomain redirect):

curl -v -L "http://localhost:8081/ipns/en.wikipedia-on-ipfs.org/I/Auditorio_de_Tenerife%252C_Santa_Cruz_de_Tenerife%252C_Espa%C3%B1a%252C_2012-12-15%252C_DD_02.jpg.webp"

For now, I've added basic unit test in ipfs-inactive/bifrost-gateway@982535a#diff-84d756d48159dd2e742a98880c23ce6d22bd80bf878409ddcf1d4dc81bc114acR38, but we should have a conformance test for this case.