Add rage to bookworm image (cargo version)

Testing recovery bundles in swh-alter requires rage and rage-keygen. See: https://github.com/str4d/rage/blob/main/rage/Cargo.toml

We use rust official Docker image to build the software via cargo install in a dedicated stage. We then copy the (statically linked) binaries to our image.

See !63 (closed) for another implementation using the .deb package provided by upstream.