An integration test builds the library without cfg(test), so it checks the release configuration: the remote agents refuse plain HTTP (an upper-case scheme too) without connecting, loopback links still work, and with local-mirror the remote agents take plain HTTP.
A refused hop's message names only the host. ureq's message holds the whole link, and a redirect to the file host carries a signed query. host() also drops a query and any user:password@.
