Update update_cached_concordances command to comply with new spec

[jacobdgm]

This PR updates our update_cached_concordances command to output a file matching the updated specification (see #1323). In doing so, it fixes #1323.

The tests have also been updated to reflect the new spec.

[jacobdgm]

I spent a few minutes looking into whether we could rename "feast__name" -> "feast" etc. within get_concordances when calculating values by using .annotate() , without having to have a separate make_chant_dict function that gets called in the list comprehension. But initial results suggest it will be tricky to create "chantlink" and "srclink" on the database level. Considering the function already takes but a couple of seconds to run, I'm thinking it's not going to be worth the trouble to apply this particular optimization. Or do any of you tagged as reviewers think this is worth looking into?

[dchiller]

Were you using concat for srclink and chantlink? https://docs.djangoproject.com/en/5.0/ref/models/database-functions/#concat I think that would be the way to do what you are referring to.

I don't feel like this is necessary unless you want to.

[jacobdgm]

Were you using concat for srclink and chantlink? https://docs.djangoproject.com/en/5.0/ref/models/database-functions/#concat I think that would be the way to do what you are referring to.

I don't feel like this is necessary unless you want to.

This is it, yes!

Maybe I'll get around to refactoring this once we've finished rolling it out as it is. For now, though, I think we're fine as-is.