Compare to previous tagged release or build

Current build artifact and log comparisons only compare to the previous build, which mainly helps discover what effects each commit/change has.

However, if one wants to review what are the changes of the current commit in comparison to the previously released version, one should be comparing to the last tagged build/release.

Note

This MR has the git tag detection right, but comparison code is just duplicating previous release logic and should be refactored. Also the comparison of build artifacts would also further needed to be normalized on version strings, as otherwise the diff does not know that it indeed is comparing the different versions of the same files.