Determine why new SOUND tests do not work in CI, and add them back.

[mkilgore]

Tests for #171 were written and planned to be added, but unfortunately they do not pass in CI. Investigation needs to be done into why adding new sound-based tests causes issue on Linux.

I added the first sound-based testing in #164, and to get it working on Linux I had to install and start pulseaudio as a way to get a fake ALSA card in place. The Linux build agents do not have any ALSA sound cards by default, so trying to use any sound-related functionality produces an error - running pulseaudio to get a fake ALSA card in place fixes the issue. It seems likely that something isn't quite right with this approach though, because the new sound tests cause the other sound-based tests to again hit the issue of no sound card being on the system. Presumably pulseaudio stopped working, removed it's fake sound card, or something else to that effect.

I was able to recreate the issue in my fork so it seems very consistent (ignoring the failures in Windows/Mac, that branch doesn't have the changes from #171 that make the tests pass). That should make it reasonably easy to test things and determine the issue. Unfortunately the biggest issue is that I never found a better solution to getting an ALSA card in place beyond pulseaudio, so it might be hard to find an alternative if that's the problem.