Code review comment for ppa-dev-tools:tests-dashboard

Noted on the refactoring change. I often squash things together in hopes it makes stuff easier to review, so it's good to know when it doesn't.

With bfd3865, it wasn't just a parameter name change, the type also changed from a string to a list. Normally I would have just pluralized series but since it's the same word singular or plural that would just be confusing, thus the name change. In hindsight, probably better to rename series->release and then to releases.

Thanks again!