GANGLIA MONITOR CORE

Forked from ganglia/monitor-core via efposadac/monitor-core which implemented python3 patches.

rpmbuild_alma9 branch

Fixes ganglia.spec.in for rpmbuild on Alma Linux 9 and compatible EL9
Adds custom ganglia_atds.spec.in file for legacy compatibility (derived from old EPEL spec), to support @AtlasTdaqSysAdmins in the migration to Alma Linux 9 and Prometheus/Grafana
Adds automated GitHub Actions for building RPM packages for Alma Linux 9, using a fork of naveenrajm7/rpmbuild adapted for Alma9 and some additional functionality