* add github actions config
As travis stopped be free for all - lets move to github actions.
- Add ruby 3.0 to build matrix
- using DymnaDB ready made action installer did not work - could work with some more time for investigation. But it works the old way.
* Re-enable codecov
* run github actions on ubuntu 20.04
* cleanup build matrix
- remove old minor rails versions 5.0, 5.1
- remove EOL ruby version 2.5
* cleanup gemfiles and Appraisal
remove unused gemsets
* add truffleruby to github actions
* use compact yaml syntax
