Add release binaries that bundle deps

In order to aid https://github.com/bootcrew/ we should generate binaries that include bundled dependencies:

- bootupd
- ostree
- skopeo

Implementation wise...what may be best here is actually that we have e.g. `/usr/lib/bootc/bundled/bin/skopeo` or so and we ensure that `/usr/lib/bootc/bundled/bin/` is prepended to our `$PATH` instead of trying to literally link in the binaries. For ostree we'll also want to inject an rpath into our executable for `/usr/lib/bootc/lib`.

(Of course this job should run on every push to main too, not just release jobs, but what most will care about is the release jobs)