Checks for updates on RPM-based distributions via yum.
Inspired by https://github.com/lgbff/lgb_check_mk_plugins/tree/master/aptng.
See https://docs.checkmk.com/latest/de/mkps.html#H1:Installation,%20Update%20and%20Removal for details on Check_MK package management.
Now built by GitHub Actions.