[WIP] disable unrelated tests

Author: ekohl

.github/workflows/ruby_tests.yml

@@ -29,20 +29,13 @@ jobs:
   - job: copr_build
     trigger: pull_request
     targets:
-      rhel-8:
-        additional_modules: "foreman:el8"
-        additional_repos:
-          - https://yum.theforeman.org/releases/nightly/el8/x86_64/
       rhel-9:
         additional_repos:
           - https://yum.theforeman.org/releases/nightly/el9/x86_64/
     module_hotfixes: true
   - job: tests
     trigger: pull_request
     targets:
-      rhel-8-x86_64:
-        distros:
-          - centos-stream-8
       rhel-9-x86_64:
         distros:
           - centos-stream-9