CI Build Fixes

This MR fixes several technical debt issues surrounding CI/CD. It migrates our backend image to Alpine and fixes outstanding test issues that caused false passes previously.

Supporting information

• #144
• #137

Testing instructions

Step by step procedure

1. Switch to this branch.
2. make destroy
3. docker compose ps -a to verify there are no containers, running or stopped.
4. make build to forcibly trigger a rebuild of the container images, since the old version will still be cached.
5. make to do the oneshot sequence
6. Verify everything is running correctly.
7. make test to run all tests.
8. make quality to verify quality.

Author notes and concerns

It looks like the issue with frontend formatting no longer failing tests has been fixed, though I'm not sure when. If you want to test this, try creating an MR based on this one, save for a frontend formatting issue, and verify the frontend failure.