[JIRA] (OVIRT-1670) Use cleanup_slave.sh and globale_setup.sh on pipeline loader nodes

Use cleanup_slave.sh and globale_setup.sh on pipeline loader nodes ------------------------------------------------------------------ Key: OVIRT-1670 URL: https://ovirt-jira.atlassian.net/browse/OVIRT-1670 Project: oVirt - virtualization made easy Issue Type: Improvement Components: oVirt CI Reporter: Barak Korren Assignee: infra Labels: change-queue, jenkins, standard-ci Pipeline loader nodes are the nodes (slaves) used to loader pipeline code and sometimes also perform some logic. The '{{global_setup.sh}}' and '{{global_cleanup.sh}}' scripts are designed to run on all nodes and prepare them for running jobs. Since the pipeline loader nodes are allocated and used differently then typical nodes that run STDCI logic, the '{{global_setup.sh}}' and '{{global_cleanup.sh}}' scripts were not used on them so far. This has caused some issues, like for example change-queue logic failing when manual changes were made to slaves. It is desirable to use the same setup and cleanup logic for all nodes regardless of what they run. Within the scope of this task, we'll also remove the custom node setup logic in the change-queue jobs and move it to '{{global-setup.sh}}' where it aught to be. This ticket is a blocker to OVIRT-1486 ATM because the custom node setup code in the change-queue jobs prevents other jobs from running parts of the change-queue logic.