The usual stuff! Installed the new gem and its new deps, ran
`bin/rails app:update` and did my best to manually merge the dev/prod
config files with the new canonical defaults, deleted some migrations I
don't think are relevant to us, and yeah!
Also, Rails 7.1 seems to need `libyaml-dev` installed, so I added that
to the `deploy/setup.yml` playbook!
One thing to note is that, while I was here, I turned on some settings
relating to our use of SSL that technically weren't on before. This
should be fine and helpful? But if stuff breaks, well, check those!
Whew! Seems like a pretty clean one? Ran `rails app:upgrade` and stuff, and made some corrections to keyword arguments for `translate` calls. There might be more such problems elsewhere? But that's hard to search for, and we'll have to see.
