Buildable with Go 1.17? Packages?

It looks like this hasn't been updated in a while, but there's still a need for this package. I can't build it on Debian Bullseye right now with Go 1.17. Unfortunately I'm not very familiar with Go so I can't really say what the problem is exactly or fix it myself. When I tried cloning the repo and running make, I just got:

```
go build -o bin/cfd+https ./cmd/cfd
go: cannot find main module, but found Gopkg.lock in /home/ryan/src/third-party/apt-transport-cloudflared
to create a module there, run:
go mod init
make: *** [Makefile:39: bin/cfd+https] Error 1
```

Ideally I'd like packages of this in https://pkg.cloudflare.com/ (and I'd like that repo updated to have bullseye packages - it's been out for some time now)