fully skip installer role when start == intermediate

otherwise it'd still try to `yum update` and run into issues

pipelines/upgrade/05-server_to_intermediate.yml

@@ -21,4 +21,4 @@
       scenario_version: "{{ forklift_upgrade_version_intermediate }}"
     - foreman_server_repositories
     - role: foreman_installer
-      foreman_installer_skip_installer: "{{ true if forklift_upgrade_version_start == forklift_upgrade_version_intermediate else false }}"
+      when: forklift_upgrade_version_start != forklift_upgrade_version_intermediate