Fix Dockerfile-dev, update Codespaces readme

[pjanik]

The Dockerfile-dev was no longer working, so I've made it more similar to the recently updated Dockerfile. The most significant change is switching to Alpine Linux. Essentially, I'm installing the same dependencies as in Dockerfile, plus bash (since Alpine doesn't include it by default, and its absence crashes some dev startup scripts).

I commented out the Google Chrome installation, as it would require some time to learn how to do it on Alpine Linux. However, I did manage to successfully run both docker/dev/run-spec.sh and docker/dev/run-cucumber.sh (although it appears that most of them are skipped). So, I'm wondering if we actually need Chrome at all?

Also, I've removed docker login command from GH Codespaces readme as it's no longer necessary.

[scytacki]

Seems fine to me. We can figure out the Chrome issue if we need it again.

I'm not sure what the status of the cucumber/jest tests that use selenium is.