We now test everything but 1.9 with GitHub Actions. GH Actions doesn't support
1.9 out of box and I am not sure how to write a spec that would use our custom
Docker image for 1.9 and the standard images for everything esle. That's why
CircleCI does not go away (for now, until we still support 1.9).
Luckily, I was able to get rid of the custom Docker image for 2.0 because GH
Actions stil support that version of Ruby.
Now the build code is much simpler and easier to follow. Looking forward to
getting rid of CircleCI completely!
Spec started failing because a statement which we expected to be a
syntax error is now interpreted as a valid pattern-matching statement.
Swapping the hash-rockets for colons turns this back into a syntax
error.
CircleCI doesn't provide images for these Rubies since they are no onger
suported. I had to build them manually and push to dockerhub so we can continue
testing using those Rubies.
I am committing these Dockerfiles since they belong to this project and in case
we need to modify them.
