Update packit to build on RHEL 8 & 9

Author: ekohl

.packit.yaml

@@ -28,11 +28,16 @@ jobs:
   - job: copr_build
     trigger: pull_request
     targets:
-      centos-stream-8:
+      rhel-8:
         additional_modules: "foreman-devel:el8"
         additional_repos:
           - https://yum.theforeman.org/releases/nightly/el8/x86_64/
           - https://yum.theforeman.org/plugins/nightly/el8/x86_64/
+      rhel-9:
+        additional_modules: "foreman-devel:el9"
+        additional_repos:
+          - https://yum.theforeman.org/releases/nightly/el9/x86_64/
+          - https://yum.theforeman.org/plugins/nightly/el9/x86_64/
     module_hotfixes: true
 
 srpm_build_deps: