Upgrade to current tumbleweed dependencies

[beatgammit]

When trying to test #248, I had trouble getting the right versions of things. The version of bundler used was newer than Leap 15.6, but older than Tumbleweed, which didn't really make sense to me.

This builds for me on a minimal Tumbleweed install (tested w/ distrobox in Aeon).

I'm not sure how the current development process works, but this will require whatever the deploy process is to be updated.

[cboltz]

The current deployment runs on Leap 15.6 + ruby 3.1.6 from devel:languages:ruby.

Is there a good reason (besides "it's newer") for switching to a newer ruby version?

[beatgammit]

I'm not a Ruby dev and it was mostly confusing to me to figure out how to get the site to render. The instructions didn't work for me with the repo version of ruby/bundler in either Leap or Tumbleweed, and I didn't see any documentation saying which version to use.

So I figured I'd try upgrading to what's in Tumbleweed to see how much work it would be (seemed reasonable since the direction for openSUSE seems to be pushing toward Tumbleweed/MicroOS/etc), and that's where this PR came from. I actually started building a podman container for it, but figured that was going a bit too far.

If the project wants to stick w/ Leap 15.6 + ruby 3.1.6, that's fine, I can update the README with those instructions. If we want a container for it, I'm happy to contribute that as well.

I opened this PR mostly because I had to do this on the way to contributing my other PR, and figured I'd submit it in case there was any interest in upgrading.