Community releases

[jacobbaungard]

This PR facilitates community releases of Merlin. A short overview of changes made are below, but please see individual commits for the details.

• op5 specific specfile moved to op5build
• added a spec file for building on Open Suse Build Service (OBS)
• Many hardcoded OP5 specific paths in the mon apps has been changed to use values set using configure (including fixing: https://github.com/ITRS-Group/monitor-merlin/issues/115)
• Fixed user/groups in systemd and logrotate configurations
• removed mon log fetch (broken) and mon log sortmerge (not used anymore)
• Added a github workflow that runs when a tag in the correct format is added. It builds the release on OBS and publishes a Github release with the built release attached
• Added a proper changelog file

Internal OP5 Jira: MON-12869