RHEL Scheduler Provisioning Fails

Provisioning version cyclecloud-gridengine 2.0.13 fails on a RHEL scheduler due to the [scheduler.rb](https://github.com/Azure/cyclecloud-gridengine/blob/66dfc1ae837d8198a1bed53b15c0e4f57c4e35ae/specs/default/chef/site-cookbooks/gridengine/recipes/scheduler.rb#L32) file line 32 where it tries to install the epel-release package. Jetpack.log error messages:
```
2022-09-12 18:16:48,120 ERROR Software configuration failed: Chef::Exceptions::Package: yum_package[epel-release] (gridengine::scheduler line 32) had an error: Chef::Exceptions::Package: No candidate version available for epel-release
2022-09-12 18:16:48,120 ERROR Recommendation: Review local log files on the VM at /opt/cycle/jetpack/logs
```
The prior change to this file for [almalinux support](https://github.com/Azure/cyclecloud-gridengine/commit/66dfc1ae837d8198a1bed53b15c0e4f57c4e35ae) changed the switch from 'centos' to 'rhel'. In moving from version 2.0.11 to 2.0.12+ this code now executes on a rhel VM whereas previously it was disabled. However, to install the EPEL repos on Red Hat the [repository must be added](https://docs.fedoraproject.org/en-US/epel/#_el7) manually instead of installing the epel-release package as in Alma/CentOS/Rocky.

Cluster Information:
cyclecloud-gridengine version: 2.0.13
scheduler image: RedHat:RHEL:7_9:latest
gridengine version: 2011.11j (DRMAA Java API added)
base template: altair-grid-engine (we are using a customized template built off the base altair template)

Commencez à la ligne 32 de specs/default/chef/site-cookbooks/gridengine/recipes/scheduler.rb et examinez la branche package-install pour RHEL ainsi que les cas AlmaLinux/CentOS/Rocky. Utilisez l’erreur de Jetpack.log et les détails de la RHEL 7_9 scheduler image pour reproduire ou valider l’échec. Le travail est terminé lorsque le provisionnement n’échoue plus lors de la configuration d’EPEL sur RHEL.

Rédigé par le modèle d'indexation à partir du texte de l'issue.