Evaluate using httpredir.debian.org

Now that we’re using torsocks for APT, it might be that httpredir.debian.org will work for us where cdn.debian.net and older flavours of it didn’t. We should test this both inside the ISO, and for the build system.

Feature Branch: feature/9235-httpredir.debian.org

Related issues

Related to #8198 (closed)

Original created by @intrigeri on 9235 (Redmine)

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information