github workflow and ubuntu-latest

[drowe67]

While working on #63, the github workflow choked when trying to install the octave-dev package when using ubuntu-latest (version 24). Changing the Ubuntu version to 22.04 fixed the problem, and the workflow ran OK. This is unfortunate, as we'd like to keep up to date with the latest Ubuntu.

The fix should:

1. Work with earlier, still common Ubuntus (e.g. 22.04, maybe even 20) that use octave-dev
2. Work with ubuntu-latest

[tmiw]

List of *octave-dev packages

Might be enough to just update the package name in the workflow? That will at least provide good confidence of it working for 22.04+ (20.04 is about to leave the standard support period).