Unfortunately `podman volume` and `docker volume` are not identical,
podman will (sensibly) error if you try to create a volume that already
exists unless you pass `--ignore`, which docker doesn't support and is
only in podman 4.4+.

So we check with `$DOCKER_BIN inspect` first and only create the volume
if necessary.

And apply the same changes to `make clean` as well.

Co-authored-by: deeplow <[email protected]>

The authenticated onion service stuff is still unmerged
(<https://gitlab.torproject.org/tpo/core/arti/-/merge_requests/2266>),
so we build Arti from the MR and it works! Generating a config.toml file
seems much cleaner than adding to `torrc` and generating `.auth` files.

The main upside for this is that using Arti is cool and gets it more
real-world testing. But the downside is that it takes a non-trivial
amount of time to build Arti locally and maybe it's not worth doing
until we have pre-package/downloadable binaries. 🤔