Migrate to GitHub actions

[mhutter]

• [x] Run yamllint
• [x] Do an Ansible syntax check
• [ ] Ping Ansible Galaxy on new tags
• [x] Bonus: Generate Changelog from Pull Requests on Github using something like mikepenz/release-changelog-builder-action

See old travis.yml:

https://github.com/mhutter/ansible-docker-systemd-service/blob/3b8da4bbc840c542ef0d46815890ad58a5e17cc8/.travis.yml